97 a1976).pdfare prescribed in TM 9—1300—206, TM 9—1375—213—12, and FM 5—25. g. Misfires. (1) Only ONE person should approach a misfired charge, and then only after an

/■

/97¿ a /

FIELD MANU

NO. 5-34

CHAPTER 1

Section I II

Section I II

III IV

CHAPTER 3

Section I II

III IV

CHAPTER 4

Section

HEADQUARTERS DEPARTMENT OF THE ARMY

Washington. D C.. 24 September 1976

ENGINEER FIELD DATA

Purpose and Scope 1 — 1, 1—2 References . . A ! 1-3, 1-5

CHAPTER 2. EXPLOSIVES ANB DEMOLITIONS

INTRODUCTION

Paragraph

Introduction \. 2-1 - 2—5 Demolitions ObstaclesV 2-6 - 2—10 Charge Calculations . A. 2—11 — 2—15 Rock Breaking/Ditching/^tumpmg . .2—16 — 2—19

LANDMINE WARFARE

Introduction \ 3—1 —3—3 Minefield Installation \ 3-4 —3—6 Reporting and Recording . . . A 3—7, 3—8 Removal of Mines \ • • • .3—9 — 3—14

FIELD FORTIFICATIONS

General Data V ... 4—1,4—2 Types of Fortifications \. .4-3 —4—6 Barbed Wire Entanglements M—7 — 4—22 Expedient Obstacles \ . . . . 4—23

Page

3 9

21 35

40 54 64 68

84 85

105 117

This manual supersedes FM 5—34, 12 December 1969. with au changes.

CHAPTER 5. MARKING OF BRIDGES AND VEHICLES

Section I. Bridges 5—1 124 II. Vehicles 5-2 - 5—3 127

CHAPTER 6. FLOATING EQUIPMENT

Section I. Bridging and Rafting Equipment 6—1—6—4 131 II. Anchorage System 6—5 — 6—7 149

CHAPTER 7. FIXED BRIDGES

Section I. Nonstandard Bridge Design 7—1—7—5 168 II. Bridge Classification 7—6 — 7—8 199

III. Standard Bridges (Bailey and MGB) ..7-9 — 7—15 205 IV. Miscellaneous Bridging 7—16 — 7—20 212

CHAPTERS. CONCRETE CONSTRUCTION R-1 - 8-8 217

9. MILITARY ROAD CONSTRUCTION .9-1 - 9-7 229

10. ARMY AIRFIELDS, HELIPADS AND HELIPORTS 10-1 - 10-10 256

11. RIGGING 11-1 - 11-17 271

12. UTILIZATION OF HEAVY EQUIPMENT 12-1 - 12-7 295

13. FIELD SANITATION 13-1-13-3 304

14. RECONNAISSANCE 14-1 -14-11 310

15. COMMUNICATIONS 15-1 - 15-5 341

16. MISCELLANEOUS FIELD DATA .16-1 - 16-17 348

a. Weights and specific gravities 16-1 348 b. Water 16-2 348 c. Construction Materials 16-3 — 16-5 351

d. Camouflage 16—6 361 e. Vehicle Recovery 16—7 367 f. Flame Field Expedients 16—8 370 g. Trignometric Functions & Volumes . 16—9, 16—10 375 h. Troop Movement 16—11 380 i. Infantry Weapons 16—12 380 j. Requests for Artillery Fire 16—13 386 k. Map Reading 16-14 391

L. Project Management 16—15 398 m. Conversion Factors 16—16— 16—18 399

APPENDIX A: REFERENCES A—1 — A—6 416

INDEX 420

CHAPTER 1

INTRODUCTION

Section I. PURPOSE AND SCOPE

1-1. PURPOSE

The purpose of this manual is to provide pertinent data in a convenient format for officers and noncommissioned officers at the platoon level.

1-2. SCOPE

a. Contents. Data has been condensed on a wide variety of subjects. These subjects apply especially to the duties of engineer unit personnel, particularly officers and noncommissioned officers in combat Engineer units where mobility is important and the constantly changing missions prevent the use of other references.

b. Comments. The proponent agency of this publication is the United States Army Engineer School. Users of this manual are encouraged to submit comments or recommendations for changes to improve this manual. Comments should be keyed to the specific page, paragraph, and line of text in which the change is recommended. Reasons will be provided for each comment to insure understanding and proper evaluation.

Comments should be prepared using DA Form 2028 (Recommended Changes to Publications) and forwarded directly to the Commandant, U.S. Army Engineer School, Fort Belvoir, Virginia 22060.

1

Section II. REFERENCES

1-3. MANUALS

Pertinent manuals and other militan/ publications are listed In the appendix.

1-4. STANDARD AGREEMENTS

Information in this manual reflects the application of Standard NATO Agreements (STANAG). Applicable STANAG's can be found in the appendix.

1-6. SYSTEM OF MEASUREMENT AND ABBREVIATIONS

In accordance with AR 310—3, linear distances used in tactical situations are expressed in the metric system throughout the text. Dimensions of a technical nature are expressed in the English system of measurements. Webster's standard abbreviations, such as "km" (kilometers), "m" (meters), "ft" (feet), and "mi" (miles) are used to clearly identify measurement units. A pace or step in marching (referred to as pace in STANAG 2036) is defined as three-quarters (0.75) of a meter (30 inches). Additional conversion factors are included in tables 16—18 and 16—19.

CHAPTER 2

EXPLOSIVES AND DEMOLITIONS

Section I. INTRODUCTION

2-1. CHARACTERISTICS OF EXPLOSIVES

<2 Demolitions are primarily used for the rapid creation of obstacles, the reduction of enemy obstacles, and construction blasting. The primary advantages are the limited logistical support requirements and the short time and small crews needed for emplacement and detonation.

b See table 2-1 for primary uses of U.S. Military Explosives, and relative effectiveness (RE) factors.

2-2. PROBLEM-SOLVING FORMAT

a Evaluate the mission and determine the results desired. b. Determine the types and quantity of explosives available. c. Identify and measure critical dimensions. d Determine the size of the charge(s). The formulas used in this chapter

give the weight of explosive (P) required for a demolition task in pounds of TNT. Where any explosive other than TNT is used, the required pounds of explosive are obtained by dividing P by the relative effectiveness factor (RE) for the explosive used (see table 2—1).

If results require a fraction of a package, round up.

Example: P(TNT) = 20 lbs (taken from table or chart)

p<C-4) =r~S= 14.91 lbs of C—4 1.34

Using M—112 blocks (1% lbs each ) 14.91 ~ ~ = 11.9 blocks, use 12 blocks

1.20

3

4

e. Determine the total number charges needed. f. Determine total amount of explosive required. {Size of charge) x (no.

of charges needed) + (explosives required for priming) = total explosives required. (Must be computed for each size charge if more than one size charge is used.)

Z- Calculate safe distance. See paragraph 2—3 and table 2—2.

Table 2-1 Characteristics of U S Military Explosives

Explosive Usags Dst. Vsl. <fps)

RE Factor

Size. Wgts, & Packaging

Breaching 1 lb 48-56/Box, Vt lb- 96-108/Box

Tetrytol Breaching 23,000 8-2% Ib/Sack, 2 Sacks/Box

C-4 M5A1 & Ml 12

Cut & Breach

M5A1- 24-2% lb Blks/Box Ml 12 30-TA lb Blks/Box

Sheet Exp Ml 18

M186

Cutting 4—% lb Sheets/Pack W/20 Packs per Box H Sheet * 3" x %” x 12") 3—25 lb Rolls/Box (50' long)

Dynamite Ml Qry/Stump/ Ditch

100-% lb Sticks/Box

Priming 20,000- 24,000

3-1000' Rolls or 8-500' Rotls/Box

Crater Charge 8,900 1—40 lb Cannister/Box

Bangalore Ml A2 Wire & Breaching

25.600 10—5' Sections/Box (176 lb)

Shaped Charges M2A4 M3A1

Cutting Holes 25.600

25.600 1.17 1 17

3-15 lb Shape Charges/Box 1—40 lb Shape Charge/Box

NOTES 1. Dynamite which is to be submerged under water for a period exceedim.

24 hours must be waterproofed by sealing in plastic or dipping in pitch. 2. C—4 which is to be used under water must be kept in packages to pre-

vent erosion. 3. Cratering charges will malfunction if the ammonium nitrate is exposed

to moisture.

Table 2—2. Minimum Safe Distance for Personnel in the Open

POUNDS OF

EXPLOSIVE

SAFE DISTANCE (METERS)

SAFE DISTANCE

(FEET)

POUNDS OF

EXPLOSIVE

SAFE DISTANCE (METERS)

SAFE DISTANCE

(FEET)

1 to 27 30 35 40 45 50 60 70 80 90

100 125

300 311 327 342 356 369 392 413 431 449 465 500

985 1020 1072 1121

1168 1210

1285 1352 1413 1470 1525 1640

150 175 200 225 250 275 300 325 350 375 400 425

532 560 585 609 630 651 670 688 705 722 737 750

1745 1831 1919 1997 2066 2135 2198 2257 2312 2365 2420 2460

Note All safe distances are determined through use of the following formula and are based on normal expected missile hazard rather than blast effect. Metal fragments can exceed the above distances and require maximum cover.

Safe Distance (meters) = 100 Pounds of Explosive

Safe distance using missile—proof shelter = 100 meters

5

2-3. SAFETY

a. Refer to AR 385—63 for necessary safety precautions pertaining to the use of explosives.

b. Refer to FM 5—25, Explosivesand Demolitions, for use of explosives by US Army personnel.

c. Report receipt of damaged or otherwise unsatisfactory explosive material on DD Form 6 in accordance with AR 700—58.

d. Report malfunctions in accordance with AR 75-1. e. Detonation or burning of ANY explosive releases toxic gases which

should not be inhaled. Burning of explosives as a source of heat or for cooking is strictly prohibited since serious illness, injury, or death can be expected.

/. Specific safe practices for handling, transporting, and firing explosives are prescribed in TM 9—1300—206, TM 9—1375—213—12, and FM 5—25.

g. Misfires. (1) Only ONE person should approach a misfired charge, and then

only after an appropriate “cook-off" time has lapsed (minimum of 30 minutes for all nonelectrically primed charges and buried charges).

(2) Misfired charges above ground should be blown in place with 1 lb of explosive.

(3) Misfired charges which are buried should be carefully excavated to no closer than 1 foot from the charge and then blown in place with at least 2 lbs of explosive.

(4) Never abandon misfired explosives. (5) Never attempt to move or disarm misfires.

h. ¡HJTNFLT EX PLOSI ~E S^ÄRTFÜLLYTD^ NO CH AN CE si]

2-4. METHODS OF PRIMING

a Detonating cord priming is the use of detonating cord to initiate an explosive charge. When used as a primer, it is not considered as part of the charge it initiates. Detonating cord is initiated as part of either an electric or nonelectric firing system, h is the most simple, saje, and versatile method oj priming. See figure 2—1

•h)

8 wraps minimum

ULi KNOT

ELECTRIC OR NON'ELECTRIC

Figure 2—1 Detonating cord priming using plastic explosives.

b. Electric priming is the use of an electric cap to initiate an explosive charge. It has the advantage of command detonation but requires additional equipment.

c. Nonelectric priming is the use of a nonelectric cap to initiate an explosive charge. It cannot be command detonated but requires less equipment than electric priming.

d. All explosive charges should be dual primed to insure detonation. See paragraph 2—5.

7

8

2-5. FIRING SYSTEMS

A firing system is a complete means of detonating a charge and includes a primer. A dual- firing system is two completely separate firing systems, each of which can detonate the charges. Possible dual systems are:

a. Dual Electric. b. Dual Nonelectric c Combination Dual System (l Electric, I Nonelectric) (fig. 2—2).

CAP LEAD WIRES

TIES

DETONATING CORD

RING MAIN-

FIRING WIRE c*

O- <■>

NON ELECTRIC

BLASTING CAP

BLASTING MACHINE

TIME FUZE

FUZE LIGHTER

GIRTH HITCH WITH ONE EXTRA

TURN TO CONNECT BRANCH LINE

Figure 2-2 Combination duet-firing system.

Note. The hazards of induced current prematurely detonating electric blasting caps may be reduced by following the precautions outlined in FM 5—25.

Section II. DEMOLITION OBSTACLES

2-6. OBSTACLE PLANNING CONSIDERATIONS

a. The combat mission of the unit being supported. b. Any limitations or instructions issued by higher authority. c. The current tactical and strategic situation.

( 1 ) The length of time the enemy must be delayed. (2) The time available to prepare the obstacle. (3) Direct and indirect supporting fires available.

d. Tie in with other natural or man-made obstacles and plans for “ffective covering fire.

e. Requirements for lanes and gaps and concealment of mines. /. The manpower needed to guard and maintain the demolitions while

awaiting authority to fire. g. The materials and equipment available. h. The possibility that friendly forces will soon reoccupy the area and

require the obstacle to be neutralized. / The immediate and long term effect on the local population.

2-7. BRIDGE DEMOLITION

Generally, bridges are demolished to create obstacles which delay the enemy; however, bridges seldom require complete destruction. The method used for demolition should normally permit the economical reconstruction of the bridge by friendly troops in future operations. Normally, the needed delay can be obtained by blasting a gap that exceeds the capability of the prefabricated high-speed bridging available to the enemy where the construction of an intermediate support will be difficult or impossible. All bridges, because of differences in size, design, and construction materials present Individual peculiarities and problems which must be considered, such as

a. How are the spans of the bridge supported and what will be the results of cutting each at various points?

b. Which parts will be easiest to cut with demolitions, what is the extent of desired destruction, and what will be the difficulty of repair?

9

10

c. What are the desired points of cut (figs. 2—3 through 2—20)? (Consider the special means of cutting each type of span.)

(1 Has each member in the plane of cut been identified and measured? e Is the problem- solving format being followed? See paragraph 2—2. /'. Who has authority to detonate or disarm? g. Destroyed span should be hardest for enemy to replace. h. Single abutment destruction should be the friendly side. /. Piers should be breached at an angle. /. On very large bridges, consider creating a gap in the approaches

instead of the bridge.

2-8. BRIDGE SPAN TYPES

a. Multiple Simple Span (fig. 2-3). Mid—span is most critical point and span ends are normally unsecured. If the gap is shallow, multiple cuts are needed to insure dropping the span completely. If necessary, two or more spans and piers can be cut to obtain the needed gap.

CUT CUT

Figure 2-3. Multiple simple spans

b Continuous Span (/¡g 2-4). Cut at both ends of a span to release a section.

CUT

X g 1 I H Figure 2—4. Continuous span.

c. Cantilever With Suspended Span (fig. 2—5). Suspended span may be pin connected.

CUT

‘h

Figure 2-5 Cantilever with suspended span.

2-9. SPAN ANALYSIS

a. Timber Spans. Cut stringers using timber cutting calculations. b. Steel Stringer Span (fig. 2—6). Cut stringers at different lengths near

the plane of cut.

11

12

CHAKOEI SHOULD II STAOOIIIO TO CUT STIINOllS

DIPMIINT IINOTHS

Figure 2—6. Steel stringer span.

c. Through Truss (fig. 2-7). (1) Method 1 — cut all members where intersected by the plane. Cut

in three places if the gap is shallow. (2) Method 2 — if clearance below the bridge is more than the

maximum diagonal truss height (D), four charges, placed on the upstream side at the points marked with an “x," will rotate and totally destroy the span.

METHOD #1 CUT ON

.PLANE

CUT METHOD #2

Figure 2— 7. Through truss

d. Deck Truss (fig. 2—8). Cut the same as the through truss.

CUT CUT

Figure 2—8. Deck truss.

13

14

e. Plate Girder (fig. 2—9). (1) Method 1 — totally cut one girder at A and one at B for total

destruction. (2) Method 2 — cut both girders at either A or B for deep gaps.

CUT CUT

t ♦ i iX *

PLACEMENT

B Figure 2—9 Plate girder.

f. Concrete Box Beams (Long Spans) (fig. 2-10). Long prestressed box beams require special charges as the location of the internal openings cannot always be determined prior to demolition. In cases of very massive beams of this type, it may be more efficient to attack the substructure.

END VIEW

Mathod# 1

Method# 2.

7~*Txl (x) $ $ Ù □¡□iiziiDnt Figure 2-10 Concrete box beam.

(1) Method 1 — if the exact location of the webs can be determined, use shaped charges to cut all webs (fig. 2—10).

(2) Method 2 — external breaching charges can be placed at the joints between the box beams or next to the webs (fig. 2—10).

g. Filled Arch Bridge. (1) Method 1 — cut at point A with charges placed on the arch ring,

i.e., dig.down to the arch ring or place beneath (fig. 2—11). (2) Method 2 — place charges on the arch ring at points B.

CUT ARCH RING„IIT

CUT x# CUT

t A "-B B"

A - LOW ARCH X

B - HIGH ARCH Figure 2—11. Filled arch bridge.

h. Open Spandrel Arch (fig. 2—12). Cut at points A, B, and C.

CUT

CUT

A B

Figure 2-12. Open spandrel arch.

15

16

/. Concrete T Beam (fig. 2-13). Breach the top, bottom, or side, or cut beams with 40 pound shaped charge.

TOP BREACH

njTLT, V

SIDE ""TJ IJ3 BREACH I3I O

Nf 40 lb SHAPED CHARGES BOTTOM BREACH

Figure 2—13. Concrete T beam.

/. Concrete Slab (Short Spans) (fig 2-14). Top breach, bottom breach, or breach as a big box beam.

CUT

Figure 2-14. Concrete slab (short spans).

k. Concrete ¡ Beams (fig. 2-15). As a result of the thin webs and high strengths, a special means is needed to destroy these prestressed beams.

(1) Method 1 — For beams with a height of 1 meter or less, place charges as shown in figure 2-16 (side breaching charges) with 3 lbs on the bottom flange and 2 lbs on the top flange. Detonate simultaneously. Charges should be placed at mid—span to take maximum advantage of bridge weight.

(2) Method 2 - Totally destroy the web with a shaped charge placed at either the top or the bottom.

Figure 2—15 Concrete I beams fprestressed).

IIIMPOtCCD CONCKITK CUKt AND DICK

msmssio CON

KEINFOtC , mu

Figure 2-16. Concrete 1 beams.

17

18

2-10. ABUTMENT AND PIER DEMOLITION

a. Over 5 feet in thickness and over 20 feet in height (see fig. 2—17). T = more than 5 ft. Breaching formula P = R3 KC (para 2—12) Compute the charges for the river face and for behind the abutment

separately.

Number of charges (N) = W. 2R

W = Abutment width R = Breaching radius Place on both sides of abutment, as shown in figure 2—17, and fire

simultaneously.

DEPTH = T

OVER 20’

c BREACHING CHARGES

Figure 2—1 7. Abutment demolition <T> 5’).

b. Over 5 feet in thickness but 20 feet or less in height. Use the solution in 2—10a but delete the charges on the river face.

c. 5 feet or less in thickness and over 20 feet in height (see fig. 2—18). T = 5 ft. or less Space 40 lb charges, 5 ft. back from the river face, 5 ft. deep, and 5 ft

apart. Breaching charges P = R3 KC (river face)

Fire charges simultaneously.

• •

OVER 20’ 5’

G '40 Ibt

,BREACHING CHARGES

Figure 2—18. Abutment demolition (T-*Z 5').

d. Five feet or less in thickness and 20 feet or less in height. Use solution in 2—10c but delete the charges on the river face.

e. Pier Demolition. Piers must be breached on an angle and as low as possible to maximize engineer repair effort (fig. 2—19).

PLACEMENT

Figure 2— 19. Her demolition.

20

/. Counterforce Charge (fig 2—20). The counterforce charge is a pair

of opposing charges used to fracture smalt concrete or masonry cubes and cylindrical columns with thicknesses of 4 feet or less. It is not effective against reinforced concrete piers or long obstacles such as walls. P = 1% x T (thickness in feet)

Example Column 3 ft. by 3 ft. P = 1 ’/a x 3 P = 4.5 lbs total C—4 or sheet explosive (1) Round fractional measurements to the next higher foot prior to

multiplying.

(2) Divide the calculated amount of explosive into two identical charges and place opposite each other.

(3) Place cap or Uli knot in the exact rear centers of charges and detonate simultaneously.

CHARGE

DETONATING CORD

(LENGTHS OF CORD MUST BE EQUAL}

CHARGE COLUMN

y

Figure 2—20 Counterforce charge

g. Breaching Hard—Surfaced Pavements. (1) Use 1 pound of explosives for each 2 inches of pavement. Tamp

with material twice as thick as the pavement. (2) Use a shaped charge. See paragraph 2—19 for sizes.

Section III. CHARGE CALCULATIONS

2-11. STEEL CUTTING CHARGES

Optimum target to explosive contact and dimensions are the most critical factors in steel cutting. The following methods, based on explosive availability, are recommended for demolition steel cutting missions.

a. Ribbon Charge. Used on flat, structural steel (I—beams, wide flange beams, plates, etc.) up to 3 inches in thickness with the following parameters:

Charge Thickness (TJ = one—half the thickness of steel member (TJ

Te-KT,

Charge Width (Wc) = three times charge thickness (Tc) WC = 3TC

Charge Length (Lc) = length of desired cut (Lä)

(1) Charge thickness must be a minimum of Vi inch regardless of steel thickness. Plastic explosive (C-4) must be cut rather than molded to preserve explosive density.

(2) Ribbon charges may be constructed using entire sheets of Ml 18 sheet explosive or blocks of M112 C—4 explosive as long as the minimum charge dimensions are equal to or larger than those specified above in paragraph 2—1 la.

(3) Correct placement of the ribbon charge requires close target-to—explosive contact over the entire length of steel to be cut (fig. 2-21).

21

22

BEAMS LESS THAN 2 INCHES THICK: . OFFSET FLANOE CHAtOE

SO THAT ONE EDGE

IS OFFOSITE CENTER

OF C-SHAFED CHAROE

BEAMS 2 INCHES THICK OR MORE: OFFSET FIANOE CHAROE

SO THAT ONE EDOE

IS OFFOSITE AN EDOE

OF THE C-SHAFED CHAROE

PRIMING: DETONATINO CORD FRIMERS

MUST BE OF EQUAL LENOTH

Figure 2—21. Ribbon charge.

b. Saddle Charge. Used on solid cylindrical structural steel bars up to 6 inches in diameter. It is triangular in shape and 1 inch thick with the long axis equal to the bar circumference and the short axis equal to one—half the bar circumference. It may also be used on solid rectangular or square bars (up to 8 inches square) but with slightly greater charge placement difficulty. Detonation is initiated by a blasting cap or Uli knot at the apex of the long axis. The explosive should be cut rather than molded (fig. 2—22).

BASE = 'A CIRCUMFERENCE

DETONATION AT APEX THICKNESS = T

3 LONG AXIS= CIRCUMFERENCE

Figure 2-22. Saddle charge.

c Diamond Charge Used on solid cylindrical steel bars up to 6 inches in diameter. It is diamond shaped, 1 inch thick, with the long axis equal to the circumference of the bar and the short axis equal to one—half the bar circumference. It may be used on rectangular or square bars, but placement around corners is extremely difficult. It is primed at the apex of both ends of the short axis with exactly equal lengths of detonating cord in conjunction with either nonelectric caps or Uli knots. The detonating cord is then joined together at the ring main. The explosive should be cut rather than molded (fig. 2—23).

SHORT AXIS = 'A CIRCUMFERENCE A

POINTS OF DETONATION

n r THICK LONG AXIS = CIRCUMFERENCE

Figure 2-23. Diamond charge.

23

24

d. The steel cutting formula is still acceptable when only hard block explosives are available.

Steel cutting formula P = (\ )A P = pounds of TNT required 3/a = constant A = cross-sectional area of member in square inches. See problem—solving format, paragraph 2—2.

e. Rules of Thumb (Steel Cutting) Rules of thumb for steel cutting give the required explosive quantities in pounds of TNT and do not require dividing by an RE factor.

{1 ) Rails (cut preferably at crossings, switches, frogs, or curves). Cut at alternate rail splices for a distance of 500 feet.

(a) Less than 5 inches high — use Vs pound. (b) Five inches or higher — use t pound. (c) Crossings and switches — use 1 pound. (d) Frogs — use 2 pounds.

(2) Cables, chains, rods, and bars. (a) Up to 1—inch diameter — use 1 pound. (b) Over 1 inch to 2 inches — use 2 pounds. (c) Over 2 inches — use P ä (3/8)A or suitable dimensional-type

charge. (3) Note. Chain and cable rules are for those under tension; both

sides of chain link must be cut.

2-12. BREACHING CHARGE COMPUTATIONS

Breaching Formula. P = R3 KC where

P = pounds of TNT required R = breaching radius in feet K = material factor (strength); table 2- C = tamping factor; table 2—4

Note (1) For external charges based on P = R3 KC, use a minimum of 5

pounds for reinforced concrete and 3 pounds for dense concrete. (2) Round up "R" to nearest Vi foot. (3) When type of concrete is unknown, always assume it to be

reinforced.

Table 2-3. Values of K (Material Factor) For Breaching Charges

Material Breaching radius K

Ordinary earth All values 0.07

Poor masonry, shale, hardpan: Good timber and earth construction

Less than 5 ft 5 ft or more

0.32 0.29

Good masonry ordinary concrete rock

1 ft or less 1.5-2.5 ft 3.0— 4.5 ft 5.0— 6.5 ft 7 ft or more

0.88 0.48 0.40 0.32 0.27

Dense concrete first-class masonry


1.14 0.62 0.52 0.41 0.35

Reinforced concrete (concrete only: Will not cut reinforcing steel)


1.76 0.96 0.80 0.63 0.54

25

26

Tabic 2—4. Values of Tamping Factor “C”

GROUND GROUND DEEP ELEVATED SHALLOW PLACED PLACED

INTERNAL STEMMED WATER UNTAMPED WATER TAMPED UNTAMPED

— I •- R

IF THE BBEACHINO BA0IU5 IS OBCATIB THAN THE DEPTH OP WATIB. USE 3 0.

IP EOUA1 TO OB IESB THAN THE DEPTH OP WATEB. USE I 0.

b. Breaching Table. Table 2—5 gives the pounds of TNT required to breach reinforced concrete targets, calculated from the formula P = R3 KC. For material other than reinforced concrete, multiply by the conversion factor in table 2-6.

2-13. TIMBER CUTTING CHARGES

a. Test shots are made to determine the required amount of explosives to cut specific types of timber. This section provides charge calculations for initial tesr shots only.

b. External Placement. P (TNT) = . Use to cut trees, poles, piles 40

posts, beams, and other timber with external untamped charges. Use graph (fig. 2—24) to calculate amount required, and place as shown in figure 2—25 (D = diameter in inches).

Table 2- 5. Breaching Charges. Reinforced Concrete Only

THICKNESS OF

CONCKETE

(ÛJ2£jOfPLACiMINT

P5! rT-i

a

C=1.0 C=l.8 C=2.0 C=3.6

FEET

2'A

3 Vi

4Vi

5 Vi

6 Vi

7'h

15

20

22

28

35

43

52

POUNDS OF TNT

14

15

22

35

52

73

79 105

136

173

186

228 TJ7"

27

39

62

93

132

142

189

245

312

334 410

498

16

30

69

103

146

158

210

273

346

371

456

~553~

28

54

78

124

185

263

284

378

490

623

667

821

■5961 TO USE TABLEi

1. MCASUBE THICKNESS OF CONCBETE

2. DETEBMINE METHOD OF PLACEMENT

1. NOTE TNT REQUIRED ACCORDING TO METHOD OF PAYMENT

4 IF USING EXPLOSIVE OTHER THAN TNT DIVIDE BY RE FACTOR FOR All METHODS OF EMPLACEMENT EXCEPT INTERNAL

5. TO DETERMINE REQUIRED NUMBER OF CHARGE)

Nb— WHERE) W = WIDTH OF TARGET

2R R = BREACHING RADIUS (III NOTES)

|l| PLACE FIRST CHARGE "R" DISTANCE FROM END OF TARGET AND All OTHER CHARGES "2R“ DISTANCE APART.

|2| FOR BEST RESULTS PLACE CHARGE IN SHAPE OF A FLAT SQUARE

121 FOR CHARGES LESS THAN 40 LBS USE CHARGE THICKNESS OF 2 INCHES

(4) FOR CHARGES 40—200 LBS USE CHA RGE THICK NE SS OF 4 INCHES

27

28

Table 2—6. Conversion Factors For Material Other Than Reinforced Concrete

Earth

0.1

Ordinary masonry, hardpan, shale, ordinary concrete, rock, good timber and earth construction

0.5

Dense concrete, first-class masonry

0.7

c. Internal Placement. P (ANY) = £_ , Use graph (fig. 2—24) for proper 250

calculation of explosive required. (D = diameter in inches).

d. Abatis P (TNT) = IL . To create an abatis, use graph for initial 50

calculation and place as an external charge. Results should leave tree attached to stump at a height of 3—5 feet. Minimum tree diameter for an effective.abatis is 18 in: for wheeled vehicles and 24 in. for tracked vehicles (0 = diameter in inches).

e. Ring Charges. (For diameters 30 in. or less) (1) Calculations

(a) Ml 18 or M186 sheet explosive; Vi x circumference (ft) x No. wraps = lbs.

(b) C—4; 1.36 x circumference (ft) x No. wraps = lbs.

(c) As an alternate method, use P =— (D = diameter in inches) 40

(2) Placement (fig. 2—25). • (a) Explosive must be wrapped completely around timber in order

to be effective, tamp if possible. (b) Direction of fall can be controlled only with ropes and cables.

2-14. CRATERING CHARGES

a Requirements. Road craters, in order to be effective obstacles, must be too wide to be spanned by tracked vehicles and too deep and steep—sided for any vehicle to pass through them. Blasted road craters will not stop modern tanks indefinitely but are considered effective antitank obstacles if

93-

to.

• 3-

•0-

73-

70-

*5-

60

33-

30

43-

40

35

JO

35

C-4 (

tew

ndaj

CHARGE PLACEMENT

EXTERNAL ND ABATIS AND

s (UNTAMEED)

INTERNAI (TAMPED)

Sss

-30

ô BIO 2o so DIAMl 1ER (ln<h«i)

Figure 2—24. Timber curling calculations 29

TN

T |

P*«ada|

30

a. QUANTITY

NUMBER OF WRAPS OF SHEET EXPLOSIVE

DIAMETER (INCHES) I I I I I I I I 1 I" I î 'V I If n 0 10 20 30

CIRCUMFERENCE (FEET) 1 I 1 1 1 1 1 1 1-1 01334567«

NUMBER OF WRAPS OF C-4

1 2

b. PLACEMENT

LOCATION OF Cf DESIRED CUT

LOCATION OF CUT . TO ELIMINATE STUMP ^

v Aviàîr* SHEET 3 WRAPS

Figure 2—25. Timber cutting charges.

-4 2 WRAPS

:-4 3 WRAPS

the tank requires three or more passes to cross the crater. Three passes will provide sufficient time for antitank weapons to disable the tank. Road craters must tie in with natural or man-made obstacles at each end. Antitank and antipersonnel mines are often placed at the site to hamper repair operations and thus increase the effectiveness of the crater. Road craters angled at about 45° to the roadway are more effective obstacles than craters blasted perpendicular to the roadway. Holes for cratering charges may be dug by:

(1) Handtools (2) Earth auger (3) 40 lb shaped charges with a 5—ft. standoff (4) 15 lb shaped charges with a 3.5—ft. standoff

b Deliberate Crater. See figure 2—26.

END HOLES ALWAYS 7 FOOT RESULTING CRATER APPROX- IMATELY R FEET DEEP AND 2 S FEET WIDE

«F>P

'.'s'*

*0*

it t* '

Figure 2—26. Charge placement for deliberate road crater.

31

(1) Number of holes (N) = L—16 5

+ 1, where L = total length of the

crater in feet. (2) Holes are 5 feet apart with both end holes 7 feet deep; holes

alternate between 5 and 7 feet in depth, but no two 5 ft. holes may be next to each other.

(3) Place 80 pounds of explosive in 7—foot holes; 40 pounds of explosive in 5—foot holes.

(4) Excavation will result with approximately 8 feet of overblast on each end.

c. Relieved Face Crater. See figure 2—27.

(1) Number of holes (friendly side): N = (_L_1^) + where L =

length of crater in feet (5 ft. deep). Number of holes (enemy side): N — 1 (4 ft. deep).

(2) Place 2 rows 8 ft. apart, spacing boreholes 7 ft. apart in each row. See figure 2—27.

(3) Enemy side is detonated first, friendly side second with a 1 to 1)4 second delay. Insure that the first detonation will not cut the firing system on the second row.

d. Hasty Crater. Figure 2—28.

(1) Holes of equal depth spaced at 5—foot intervals: Place 10 pounds of explosives per foot of depth; resulting crater will be approximately 1)4 times the depth of boreholes and 5 times the borehole depth in width (fig. 2-28).

(2) Boreholes should be a minimum of 5 feet in depth.

(3) Number of holes = N = ~ ^ + 1 5

{4) This crater is not as effective as a deliberate or relieved face crater but is excellent when preparing surfaced areas for mining.

2 -15. DESTRUCTION OF ENEMY OBSTACLES

a. Combat Engineer Vehicle (CEV). The CEV provides engineer combat support to ground operations in the destruction and removal of roadblocks, the filling of gaps, ditches, and craters, and in performing other

SH**''

L' 40#

1 90#

msTA*“oUS

Ot'-A''

r O-Tr O

O

0*iH°U

fMU*N

Figure 2-27.

CDGE Oj

Relieved f°ce ccfftcr.

33

34

HOLES OF EQUAL DEPTH, SPACED AT 5-FOOT INTERVALS. USE 10-POUNDS OF EXPLOSIVES PER FOOT OF DEPTH. RESULTING CRATER DEPTH APPROX. 1Ï4 TIMES DEPTH OF

BOREHOLES. WIDTH APPROX. 5 TIMES DEPTH OF BOREHOLES.

FT ■V>n FT. «Ov

FT, FT.

FT

FT APP/t ox

?Fs

TO CENTER OF CHARGE

Figure 2—28. Charge placement for hasty road crater.

engineer tasks. The CEV has a 165—mm demolition gun, which has a maximum effective range of 900 meters. It can hit a 6 ft. by 6 ft. target consistently. The minimum safe distance from the impact area for personnel in the open is 1200 meters. The primary use of the gun is to remove obstacles such as roadblocks, log cribs, trees, and to destroy enemy bunkers without exposing personnel to enemy small arms fire. If a dud round occurs, the round remains armed and should be blown in place.

b. Rules of Thumb For Destroying Obstacles <Combat Situation). (1) Concrete block obstacles. Use 1 pound of explosive per cubic

foot of volume up to 100 cubic feet. (2) Log obstacles. Generally the charge should be placed at a joint.

Against log cribs, place 30 to 40 pounds of explosives in the center of the earth fill, two—thirds down the depth of the crib, and tamp, if possible. Charges should be placed at 8 foot intervals throughout the length of the obstacle. Charges placed on obstacles driven into the ground should be attached below or as close to the surface of the ground as possible.

c. Walls. (1) Concrete walls not backfilled: use breaching formula in paragraph

2-12.

(2) Backfilled walls: multiply by 1.2 the charges specified for walls not backfilled.

Section IV. ROCK BREAKING. DITCHING, AND STUMPING

2-16. BLASTING BOULDERS

See table 2—7 for charge size for blasting boulders. See figure 2-29 for placement of charges. External breaching charges may be used as an expedient.

Table 2— 7. Charge Size For Blasting Boulders

Pound* of explosive required

Boulder diameter (ft) Blockholing Snakeholing Mudcapping

3

4

5

%

V. %

2

3

2

3%

6

35

36

SNAKEHOUNG FUSE OR LEAD WIRE

TAMPING % sz

'BLASTING CAP 'EXPLOSIVES

MUD TAMPING MUDCAPPING FUSE Oß SIEAD WIRE

bun

^BLASTING CAP EXPLOSIVES

i££Oqw

FUSE OB dr* LEAD WIBE

TAMPING

ilOCKHOUNG

BLASTING CAP EXPLOSIVES

Figure 2-29. Methods of blasting boulders.

2-17. DITCHING

a. Conditions. Rough open ditches 1 to 4 m deep and 1 to 20 m wide can be blasted in most types of soil, other than gravel or sand. Trees, stumps, and large boulders are charged separately, but are fired with the ditching charges.

b. Test Shots. Before beginning the ditching, test shots are required to determine the proper depth, spacing, and weight of charges needed for the desired results.

c. Detonation. Begin with holes 2 feet deep and 18 inches apart for soft ground. The depth of the hole is normally 1 foot above the gradeline of the ditch.

d. Use 1 pound of explosive per cubic yard of material to be removed. Test and adjust as needed.

2-18. STUMPING

a. Use a ring charge at ground level if speed is important and the roots can remain in place.

b. The size of the charge required varies with the size, variety, and age of the tree or stump and with soil conditions. The rules of thumb (fig. 2—30) must be adjusted based on test results.

2-19. BREACHING HARD SURFACE PAVEMENTS

a. Shaped Charges. Table 2—8 shows the size of boreholes obtained by using the standard shaped charges.

b. If shaped charges are not available, follow instruction outlined in paragraph 2—10g. Pavement breaching charges should not be placed at an expansion joint in the concrete.

37

38

TAMPING TAMPING

I CHARGE \ CHARGE

Í s a.««s

EVENLY ROOTED STUMP LARGE ROOTS ON SIDE OF TREE

DETONATING CORD

DETONATING

ü C0RD M J CAP

TAMPING TAMPING

CHARGE \ CAP

X. CHARGE

LARGE LATERAL BRACE ROOTS

HEAVY TAP ROOT AND STRONG BRACE ROOTS

RULES Of THUMB. USE DYNAMITE AS FOLLOWS:

111 FOR DEAD STUMPS-1 POUND PER FOOT OF DIAMETER. (2| FOR LIVE STUMPS. 2 POUNDS PER FOOT OF DIAMETER.

13) FOR STANDING TIMBER - ADD SO PERCENT FOR STANDING TIMBER

Figure 2—30. Stump blasting methods for various root structures

Table 2-8 Size of Boreholes Made by Shaped Charges

16 lb. shaped charge (M2A4)

40 lb. diaped charge (M3A1)

Reinforced Concrete

Max wall thickness that can be perforated Depth of penetration in thick walls Average diameter of hole Minimum diameter of hole

36”

30”

2%”

2”

3tt" 2»

Armor Plate

Penetration

Average diameter of hole

20" (at least)

254"

3” concrete pavement with 24” rock base course

Optimum standoff Min. depth of penetration

Min. diameter of hole

354' 38” -90”

Equal to or greater than shown below for 10” concrete

10” concrete pavement with 21” rock base course

Optimum standoff Depth of penetration Min. diameter of hole

354' 44” -91”

1%'-'

5' 71" - 109”

614"

Soil 30” standoff. Diameter of hole Depth of hole

48” standoff. Diameter of hole Depth of hole

7” T

1454" 7'

Diameter of hole w/30”

standoff Depth of hole w/30” standoff Depth of hole w/42” standoff Diameter w/SO” standoff Depth w/50” siandoff

5” to 8” 6'

Diameter w/42” standoff Depth w/42” standoff

354” 7’

6"

12'

39

CHAPTER 3

LANDMINE WARFARE

Section I. INTRODUCTION

3-1. TYPES OF MINES

See table 3—1 for standard U.S. mines and firing devices.

3-2. TYPES OF MINEFIELDS AND EMPLOYMENT

Minefields are classified into five types according to their function and method of employment.

a Types (1) Protective mmejield (hasty or deliberate) No set pattern.

Antihandling devices and nonmetallic mines should not be used. Protective minefields are particularly suitable for directional mines.

(a) Hasty. Used to provide local close-in protection. Mines should be readily detectable and facilitate rapid removal by the laying unit. Boobytraps and antidisturbance and antihandling devices will not be used. Authority to lay is battalion — can be delegated to company or platoon for a specific operational mission.

(b) Deliberate. Used to provide local protection for semifixed installations. Normally, mines are buried and the minefield is semipermanent in nature. Authority to lay is the installation commander.

(2) Tactical minejield. Used to stop, delay, or disrupt an enemy attack, to reduce enemy mobility, to block penetrations, and to strengthen manned positions. May be used behind enemy forces in order to deny withdrawal, prevent reinforcement, or protect friendly flanks. Conventional mines will be laid in a standard minefield pattern, but scatterable mines may also be integrated into the minefield. Authority to lay is division — can be delegated to brigade.

Table 3-1. Mine Data

Ml4 BLAST ANTIPERSONNEL MINE

1

2

3

4

Wt 3 1/3 oz. Explosive . .1 oz. TETRYL Fuze integral

(with Belleville Spring) Functioning 20 to 35 lb. Penetrate Boot & Foot

Unscrew shipping plug from bottom of mine. Turn pressure plate to ARMED position with arming tool.

♦

Remove safety clip and check for malfunctioning.

SX Replace safety clip.

Screw detonator detonator well.

i nto

7

H Bury mine and remove safety clip.

8 TO BURY: Pressure plate should be slightly above ground level. TO DISARM: Insert safety clip and remove detonator. CAUTION: Repeated turning of arming dial may cause excessive wear.

41

41 a

Table 3-1. Mine Data (Con 't>

M1BA1 BOUNDING ANTIPERSONNEL MINES

2 Wt 8.25 lb. Projectiles Steel Fuze M605

(Combination) Functioning:

Pressure ... 8 to 20 lbs Pull 3 to 10 lbs

Bounding Ht .6 — 1.2m Casualty radius 30m

3

'JV-

Remove shipping plug and screw in fuze.

GROUND LEVEL

WM Vs

// y > >

Pressure installation

2U Tripwire installation

A

Attach tripwires — first to anchor, then to pull ring.

7

Remove locking safety pin first. The interlocking pins should fall free. Then remove positive safety.

^ TO DISARM: Reverse arming procedure.

Table .1-1. Mine Data (Con 'It

M25 BLAST ANTIPERSONNEL MINE (ELSIE)

2Wt 2 3/4 oz. Explosive ... 1/3 oz. shape

charge Fuze integral

(w/ball release) Functioning.. 14 to 26 lbs Penetrate Boot & Foot

Push mine into ground. Keep dust cap in place. If ground is hard, dig hole with bayonet.

o

'TL- V

Insert charge.

Remove safety clip.

TO DISARM: Reverse arming procedure.

Remove dust cap.

41 b

Table 3-i. Mine Data (Con’t)

M26 ANTIPERSONNEL MINE

Wt 2.2 LBS Projectiles Pellets Fuze integral Functioning:

Pressure .... 14—28 lbs Pull 4-8 lbs

Bounding Ht 3m Casualty Radius 17m

Remove arming handle. (If tripwire is to be used install trip-lever; attach slack wire to lever; and) place mine in ground flush with top of ground.

Remove arming retaining pin.

latch

Attach arming handle to lugs on arming latch, rotate the cover clockwise until it comes to a positive stop (the arrow will point to the red letter “A” armed).

Remove arming latch by pulling straight out with the arming handle.

TO DISARM: Reverse arming procedure.

Table J - /. Mme Data (Con V/

M18A1 FRAGMENTATION ANTIPERSONNEL MINE

1

ROM»

T0WAPO9

2 wt 3.5 Ibs.

Explosive 1.5 Ib. C4 Projectiles 700

(steel bells) Equipment: One electric

cap 30m firing wire per mine. One electric firing device per mine. One Tester per 6 mines.

3

TEST CIRCUIT: Mate firing device, circuit tester and blasting cap. Depress handle. Light should show in window. Separate test components.

4 AIMING. IN AIMING THE M18A1. WHEN USING THE SLIT TYPE PEEP SIGHT. AIM THE MINE AT AN INDIVIDUAL'S HEAD WHEN STANDING 45M FROM THE MINE« WHEN USING THE KNIFE EDGE SIGHT. AIM THE MINE AT AN INDIVIDUAL'S FEET WHEN STANDING 50M FROM THE MINE

5

Remove shipping plug-priming adapter, insert blasting cap and screw into either cap well.

16*

Unroll firing wire and connect directly to firing device with safety engaged.

Direction of Aim -60*

Donaefous Out 2*0 we 1er

IOO M

FIRING POSITION: A minimum of 16 meters from rear of mine to fox hole. Friendly troops at side and rear should be under cover at a minimum of 100 meters.

8 TO FIRE: Disengage safety bail and depress handle.

9 TO DISARM: Reverse arming procedure.

41 d

42

Table 3-1 Mine Data (Con't)

Ml 5 HEAVY ANTITANK MINES

o

Insert fuze

2 Wt 30 lbs. Explosive 22 lbs. Fuze M603 Secondary fuze wells ... 2 Functioning:

300 to 400 lbs.

o

Inspect fuze and remove safety.

O

Replace plug with dial in safe position.

Remove plug and inspect fuze well.

HF o

Turn dial to ARMED.

TO BURY: Put mine in hole with pressure plate at or slightly above ground level.


Table S-J. Mine Data (Con 'ti

Ml5 ANTITANK MINE USED WITH M608 FUZE

2 Functioning .. . .200-350 lbs for 250-450 milliseconds.

Resistant to blast type

countermeasures.

3 LOCKING RING-

FUZE BASE *•

Remove plug and inspect

fuze well. Insure fuze is in

SAFE position.Thread fuze

into mine HAND TIGHT

4Hold fuze to prevent

rotating, turn locking ring

down until it locks against

pressure plate.

5

. c

6

Place mine in hole and

remove pull pin from fuze.

X.

Turn dial from SAFE to

ARMED.

7 TO DISARM: Reverse

procedure except DO NOT

replace-pull pin.

42 a

42 b

Table J-l. Mine Data (Con '!)

Ml9 PLASTIC HEAVY ANTITANK MINE

2 Wt 28 lbs. Explosive 21 lbs. Fuze M606 integral

(with pressure plate) Secondary fuze wells ... 2 Functioning:

350 to 500 lbs.

Remove plate-fuze.

pressure

Remove shipping plug; check position of sinker (offset). Remove safety fork, then turn dial to ARMED position. Check position of striker (center). Turn to SAFE and replace safety fork.

Screw threaded detonator into detonator well.

o Place mine in hole, remove safety fork; and turn dial to ARMED.

Complete camouflage

TO BURY: Put mine in hole with pressure plate at or slightly above ground level.

^ TO DISARM: Reverse arming procedure.

Table S-Î. Mine Data (Con’t)

M21 METALLIC (KILLER) ANTITANK MINE

t3

Wt 18 lbs. Explosive 10.5 lbs. Fuze M607 Functioning 290 lbs.-

(Pressure on pressure ring or 20° deflection of tilt rod)

Remove closing plug, insert Ml 20 booster in bottom, and replace closing plug.

Remove closure assembly from fuze.

Remove shipping plug from mine and scruw in fuze, then screw in tilt rod extension.

& m i

Bury mine

y PI

Remove safety (pull ring assembly) and complete camouflage.

For pressure type mine bury with fuze cap flush with ground surface. Tilt Rod-mines should be seated firmly in snug-fitting hole. Most effective in tall brush or grass.


42 c

Table 3-1. Mine Data (Con't)

M21 ANTITANK MINE USED WITH M612 FUZE

1

Hss two 2.7m pneumatic leads, safety latch and arming lever.

<s>

Remove closing plug, insert M120 booster. ,i>

Remove shipping plug from mine. Screw in fuze.

Bury mine, extend hoses.

Cross and

Lift safety latch and turn arming lever to ARMED. Recross hoses.

1 Complete camouflage .

8 Timer provides a 30 i 5 minute safe separation period. Both leads must be depressed for initiation.


Table J- I. Mine Data ! Con‘t)

M24 OFF-ROUTE ANTITANK MINE INSTALLING AND ARMING

DISPENSER POUCH ACCESSORIES

POUCH

2

3

4

DISCRIMINATOR ASSEMBLY ON

SPOOL

n x M6I FIRING ASSEMBLY BIPOD

DEVICE SIGHTING ASSEMB LY

Remove above items from accessories pouch. Insert batteries (issued separately) in firing device.

DISCRIMINATOR LAID FOR TRACKED VEHICLES

y TARGET IMPACT POINT

TARGET IMPACT POINT

DISCRIMINATOR LAID FOR/ WHEELED VEHICLES

Unreel discriminator starting at far side of road (perpendicular to edge for wheeled vehicles; about 1 5° from perpendicular for tracked vehicles).

BROWN MARKS DISCRIMINATOR

FIRING DEVICE ^

Attach discriminator wire to DETECTOR of firing device (toggle switch on SAFE). Stand on two brown marks on discriminator nearest firing device. If lamp lights, circuit is good; otherwise, discard system.

43


M24 OFF-ROUTE ANTITANK MINE (CON'T)

DISCRIMINATOR

J o- 3 m to 30 m

LAUNCHER

Disconnect discriminator wire from firing device. Remove launcher from dispenser pouch and place in position. Remove packing blocks, push rocket forward to safety band, and remove band. Depress ejection pin and push rocket back into launcher until contact ring is exposed at base. Grounding clip must be connected. Remove tagged shorting clip and push rocket back into launcher. Tape plastic covers over ends of launcher.

6

Position launcher on bipod assembly or mound of earth. Mount sighting assembly and sight along discriminator to target impact point about 1m above road (soldier’s belt buckle.) To aim, move launcher, not sight. Fill poucher with dirt, lay over launcher, recheck sight, remove sight, re-connect discriminator wire to firing device (light out), connect rocket cable to firing device, and push toggle switch to ARM. The system is now armed and will fire when pressure is applied to the discriminator. See TM 9—1345—200.

43b

44

Table S— I. Mine Dala (Cnn 'll

M23 AND Ml 1 GALLON CHEMICAL LANDMINES

1

©

When armed for pressure detonation, emplace in same manner as the M15 antitank mine.

HD SAJ

Wt. I 1 lb. loaded; has a 1.2m length of detonating core for burster charge. May be armed for electric or tripwire actuation.

Electric Firing

e r Attach burst,, charge—1.2m length of detonating cord-to side of mine.

EX m Vs ///

6ury mine 10cm and attach detonatuig cord to controlled firing system.

Nonelectric Firing

n n % TfTTrh 77777 Bury mine as above and attach nonelectric detonator to burster.

8 WARNING: Soldiers preparing, laying, and removing chemical landmines, must wear protective clothing.

Table 3-1 Mine Data (Con 'll

M66 OFF-ROUTE ANTITANK MINE

1

RECEIVER ASSEMBLY

SOURCE ASSEMBLY X

DATA PROCESSOR

RECEIVER CABLE

T

ELEVATION AND AZIMUTH SIGHTING ASSEMBLY

GEOPHONE

STAKES (6)

THUMBSCREW WRENCH

OUTPUT CABLE ASSEMBLY

TEST LIGHT

LAUNCHER

Assemble tripods, source and receiver assemblies. Install battery in source

assembly.

45 a


M66 OFF-ROUTE ANTITANK MINE (CON'T)

Select well camouflaged sites across road. Aim source assembly at receiver and about

1 meter above road center. Stake legs of tripod to ground. Aim receiver at source

assembly. Connect Geophone cable, output cable w/test light, and receiver assembly cable to data processor. Install batteries in data processor. Hold Geophone steady and place hand m front of receiver. If test light functions system is operative (If light does riot function check connections and source/receiver alignment). Disconnect

Geophone and place hand in front of receiver. Test light should not function (If

light functions system is inoperative and should not be used). If light does not function connect Geophone cable and press spike into ground

Table 3-1. Mine Data (Con’t)

M66 OFF-ROUTE ANTITANK MINE (CON'T) U— 30 m or less "I

rmiiiiiiin"""!111"" el - -

/. i"

e /

i.

APD

Unwind firing cable from rocket, slide rocket forward from launcher enough to

remove safety. Depress ejection pin and slide back into launcher. Position launcher

and sight on impact point 1m above road center on source/receiver line. Secure

launcher with sandbags. Position output cable and firing cable as shown. Test light

should not function. If it does recheck connections and source/receiver alignment.

Remove shorting plug and connect cables.

4 WARNING: Make sure all personnel are clear of launcher when testing circuits.

45 b

46

Table 3- 1. Mine Data (Con’t)

Ml PULL FIRING DEVICE

LOCKING SAFETY

INITIATING ACTION: 3 to 5 lb pull on tripwire.

NONELECTRIC STANDARD BLASTING CAP

•WIRE BASE. I *

ir««Tr-i'Tn/C /'AD PROTECTIVE CAP

CRIMPERS « EXPLOSIVE

Remove protective cap from standard base and crimp on nonelectric blasting cap. Attach firing device assembly to charge. Attach anchored tripwire.

f. -oc±:

TO ARM: Remove locking safety pin first, and positive safety pin

last.

-^¿±1 POSITIVE SAFETY - '<3£

TO DISARM: Insert nail, length of wire or original safety pin in positive safety pin hole first. Then insert similar pin in locking safety pin hole. Cut tripwire, and separate firing device and expolsive. Unscrew standard base.

The Ml pull firing device can be used as an antihandling device on the M15 or M19 AT mines. The arming procedures are the same as above. The device is employed in the side fuze well and a tripwire attached from the Ml to a stake secured underground near the mine.

Table J-i. Mine DataiCon't)

M1A1 PRESSURE FIRING DEVICE

LOCKING SAFETY

POSITIVE SAFETY

Initiating pressure: 10 lbs or more.

DET CORD NONELECTRIC BLASTING CAP TAPE

CRIMPER

BASE □ COUPLING ^PROTECTIVE CAP

EXPLOSIVE

NONELECTRIC BLASTING CAP

Remove protective cap from base

and crimp on nonelectric blasting

cap. Assemble dot cord, nonelectric

blasting cap, and firing device.

SAFETY CLIP

/ POSITIVE SAFETY PIN

TO ARM: Remove safety clip.

Then positive safety pm.

kr

TO D I S A R M : Insert wire, nail,

original pin in positive safety hole.

Replace safety clip, if available.

Unscrew base assembly from firing

device.

46a

46 b

Table 3-1. Mine Data (Con'll

M3 PULL RELEASE FIRING DEVICE

1 LOCKING SAFETY

POSITIVE SAFETY

as_

2 PROTECTIVE CAP

2TV TNT

CRIMPERS


Remove protective cap and crimp

on a nonelectric blasting cap.

Attach firing device assembly to

anchored charge (must be firm

enough to withstand pull of at least

6-10 lbs. pull on tripwire). Put free

end of anchored tripwire m hole in

winch with knurled knob, draw up

tripwire until locking safety is

pulled into wide part of safety pm

hole.

TO ARM; With cord, remove small

cotter pin. from locking safety pin,

and withdraw locking safety pin. If

it dees not remove easily, adjust

winch winding. With cord, pull out

positive safety pin.

4 TO D I S ARM: THE M3 IS

DANGEROUS TO DISARM. IT

SHOULD BE BLOWN IN PLACE.

NOTE:

If the device must be disarmed

proceed as follows: Insert length

of wire, nail or original pin in

positive safety pin hole first. Then

insert length of wire, nail or original

locking pin in locking pin hole.

Disassemble tripwire, firing device

and explosive.

Table 3 - /. Mine Data (Con’t)

M5 PRESSURE-RELEASE FIRING DEVICE

RELEASE PLATE

SAFETY ^PIN

3 A/T MINE

HEAVY 1 t J W,RE-^7U-

THIN WIRE

2

INTERCEPTOR HOLE^

INITIATING ACTION:

Lifting 1.59cm or

removing restraining

weight (51b or more).


CRIMPER 7 4

TO ARM: Remove thin

wire (locking safety) and

then heavy wire (positive

safety) from interceptor

hole. FOLLOW ARMING

PROCEDURE

CAREFULLY.

STANDARDjrö BASE Cfl

LENGTH 10-GAGE WIRE.* ^ PLYWOOD PRESSURE “

BOARD

Insert length of 10-gage

wire in interceptor hole

and holding release plate

down, remove safety pin.

Replace safety pin with

length of No. 18 wire.

Assemble cap, firing device

and mine.

HEAVY WIRE

TO DISARM: Insert length

of heavy gage wire in

interceptor hole. Bend

wire to prevent dropping

cot. Proceed carefully, as

ihe slightest disturbance of

restraining weight may

detonate mine.

Disassemble firing device

and mine.

46 a

Table .1 - / Mine Data (Con‘t)

M49A1 TRIP FLARE

2 Burning period .... 55 to 70 sec

Illumination radius 300m

Initiated by taut or loose tripwire.

E t| Attach flare to post, tree, etc.

Attach tripwire to anchor, then to trigger. Pull trigger to vertical position and secure.

If?

TO ARM: Remove safety clip.

TO DISARM: Insert safety pin.

It ■Check both tripwire and trigger.

8 WARNING: Never look directly at burning flare. Note: For loose tupwire initiation, attach tripwire to eye of safety pin.

(3) Point minefield. Used to delay and disorganize the enemy or to hinder his use of key areas. Generally irregular in size and shape, ranging from a single group of mines to successive mined areas. Both conventional and scatterable mines may be employed. Authority to lay is division — can be delegated to brigade.

(4) Interdiction minefield Used in the enemy rear to harass and disrupt normal activities, and to deny the enemy the use of key facilities. Normally consists of scatterable mines. Authority to lay is corps — can be delegated to division.

(5) Phony minefield. Used as part of a barrier system to deceive the enemy when the lack of time, personnel, or material prevents the use of real mines. Effectiveness depends upon resemblance to the type of minefield being simulated. They are of no real value until the enemy has become mine conscious. Authority to lay is the same as the type of minefield being simulated.

b Employment (1 ) All minefields should be covered by fire. (2) Minefield effectiveness can be increased by varying types of

mines, fuzes, and tripwires. (3) Warning devices such as sensors, tripwires, smoke or flame devices,

and noise makers should be used to alert troops to enemy breaching attempts.

3-3. MINEFIELD PATTERNS

a Standard Minefield Pattern The standard minefield pattern is a defined regular pattern which provides optimum effectiveness against enemy passage and/or breaching. It also allows for ease of removal by friendly troops {fig. 3-1).

(1) Strip centerline A measured, predetermined line along which no mines are placed. It is paralleled on each side by two rows of mines or clusters at a distance of 3 meters (fig. 3—2).

(2) Row. A single row of mines or clusters laid in a generally straight line. Mine rows parallel the strip centerline at a distance of 3 meters (or paces) and are laid at 6 meter (or pace) intervals, (fig. 3-2)

48

MIWFIEI D FRONT ♦ t

If XPRFRSEO IN METERS) ENEMY /V

NOTE E I THF R 3 ME ^ . Cl t

□ — ? X

?N0 LANDMARK NE CORNER OF BLOC.

Figure J- I Minefield, standard flattern, fenced, marked and referenced

(3) Mim'Jield strip Two parallel rows of mines or clusters including

a strip centerline (fig. 3—2).

(4) Cluster A semicircular grouping of mines spaced along the

minefield rows at specified intervals (fig. 3-2). Clusters are numbered to aid

in identification for removal purposes and to identify those mines having

tripwires or antihandling devices (fig. 3—3).

Clusters may be either live (those containing mines) or omitted (those not

containing mines). Clusters are normally omitted because of irregularities in

the terrain. These irregularities may also necessitate a slight change in the direction of the minefield strip These changes of direction occur at turning

points, (fig. 3- 4)

(5) Irregular outer edge UOIi) The purpose of the IDE is to contuse

the enemy as to the exact trace of the minefield and to block likely avenues

of approach. There can be any number of short strips in the IOE, but they

should be no closer to each other than 15 meters (fig. 3-3).

(6) Deusin A three-number sequence depicting number and type

of mines per meter of minefield front. (1—2—2 depicts 1 AT mine, 2 APE

mines, and 2 APB mines.)

A2 CENTER LINE OF

MINE STRIP

,'u ' '• w \ LJ-o- •_»

£ T u I Í I

'ë t

Im/PACESf«.

I I

f- I

I I I

1 *7 \ /

t ENEMY

ROW 1

A1

ROW 2

4 2

NOTES: 1. AT Min* 0 AP Min*

2. Clutter with AT min« and 4 AP minas within 2m/paca wm-circt«. ^ Tj-s 2m/PACES

3. Cluster with AP bM mine and 4 addition ai AP mines.

/J’ L* a •_i 4. Within a mine strip:

|a) The number of AP mines in each cluster must be the same.

|b) Different types of AP mines may be used in a duster.

(c) Different dusters may contain different types of AT mines.

6. No duster can exceed 6 mines with only 1 AT mine per duster.

Figure 3—2. Minefield strip with strip centerline, rows, and clusters.

49

50 MARKING OF SHORT

MINE STRIPS or JOE

i?e

a [«-MINIMUM-*! 13

I 5 m MINIMUM 1& 13 n

END POINT OP

BASE UNE TO TOE

/ 's i4 i2 io \ ¿V TURNING POINT

15 13

J. J. Ij'x'lWrW 18 ^ y4'l y- V-1 r!v J, X 7i. la«" 12 10 fl 5 '*'4 '.<2 j

MINIMUM END POINTS Or MINE./ STRIP CENTERLINES --1-? 1 I

1“ ^2 ri. >6 To g - '

.. STRIP CENTERLINE^ fi Notes: 4 y

1. Marking of end points with A1 and A2, for example, will indicate laying direction of a minefield.

2. Laying will always begin at point No. 1.

3. Odd numbers on enemy side of the strip.

4. Strip start and end points, and turning points will be marked with a 2" x 2" wooden stake.

Figure Method oj numbering clusters in a mmejield

laid from right to lejt.

INC LAST CLUSTin BETÖRE AND THE FIRST

CLUSTER AFTER THE TURNING FOINT WILL HAVE A DISTANCE OF 3 METERSÂCES FROM THE TURNING FOINT ANO ARE LAID ON OPPOSITE SIDES OF THE STRIP

CENTERLINE

AN OMITTED CLUSTER IS NUMBERED WHEN IT IS NECESSARV TO MAINTAIN THE

NORMAL NUMBERING SEQUENCE AND OMITTED CLUSTERS SO NUMBERED MUST BE NOTED IN THE ' NOTES" SECTION OF THE

MINEFIELD RECORD (DA FORM 13661

W

Th« minimum dtilonc« it two m«t«r«/

poc«i er lh« clwst«r (no. IS) j* emllt«d

^ DIBECTION OP LAYING

IP THE DISTANCE 1$ LESS THAN 3

METERS/PACES BETWEEN THE LAST POSSIBLE CLUSTER AND THE TURNING POINT THE CLUSTER WILL BE OMITTED.

THE FIRST CLUSTER AFTER THE TURNING POINT WILL BE LAID ON THE OPPOSITE SIDE

OF STRIP CENTER CENTERLINE FROM THE LAST LAID CLUSTER AND THREE

METERS/PACES FROM THE TURNING POINT

clw»t«r omilt«d

3 3 I 3

< I

\Jy Th« minimwm diaton«« la two m«t«ra/

o<«a or th« clwalor (no. 19) la omiltod.

^ PHECTION OF LATINO

FIRST CLUSTER OF STRIP WILL NOT BE

CLOSER THAN 3 METERS TO THE LINE JOINING THE END POINTS OF MINE STRIPS

/MINEFIELD LANE Q IOE

Minimum 3m \

’ / W ^£7

/^Minimum 3m

• DIRECTION OF LAYING

Figure 3—4. Turning points on a minefield strip.

51

52

(7) Minefield gap A cleared area through a minefield wide enough for the passage of a friendly force in tactical formation. Width of a minefield gap is seldom less than 100 meters

(8) Minefield lane A cleared path through a minefield for passage of troops (2 meters wide) or vehicles (8 meters wide — one-way, 16 meters wide — two-way)

(9) Tripwires Tripwires are employed only with APF mines. Employment procedures are defined in figure 3—5.

1. - + - = TRIPWIRE EMPLOYED ON MINE ROW ON ENEMY SIDE OF STRIP, ONLY

2. TRIPWIRE LENGTH WILL NOT EXCEED THE CASUALTY RADIUS OF THE MINE.

3. NO TRIPWIRES IN THE IOE.

4. ONLY ONE MINE PER CLUSTER WILL EMPLOY A TRIPWIRE IFOR SAFETY PURPOSES IT IS RECOMMENDED THAT THE MINE CLOSEST TO THE ENEMY BE TRIPWIRED. BASE MINE OF CLUSTER SHOULD NOT BE TRIPWIRED.)

5. TRIPWIRES * £ 2 PER MINE.

6. TRIPWIRES WILL BE EMPLOYED NO CLOSER THAN EVERY THIRD CLUSTER.

7. TRIPWIRES WILL BE ANGLED TOWARD THE ENEMY AND WILL BE NO CLOSER THAN 2 METERS TO ANOTHER TRIPWIRE, ANOTHER CLUSTER. THE SAFETY LINE, THE IOE, MINEFIELD LINE OR GAP, OR THE MINEFIELD BOUNDARY.

SAFETY LINE AND SAFETY DISTANCES REQUIRED WHEN USING WIRE ACTUATED MINES IN MINEFIELD EN ENEMY

NOTE

b Raw Minina. Row mining is the emplacement of AT mines in a row by use of the M-57 antitank mine dispensing system (fig. 3-6).

A2 O

ENEMY

6 METERS (AT)

3 METERS (AP| B 2

Bm MINIMUM

-a DI

NOTES Distances'may vary according to the tactical objective, the technical effectiveness desired and the characteristics of the mines used, but should remain the same within one mine row.

lixtirc J-b Rmv niinina.

53

54

Section II. MINEFIELD INSTALLATION

3-4. MINE AND MAN-HOUR COMPUTATIONS

Material and manpower requirements and logistical and planning data are found in tables 3—2 and 3—3.

Table 3—2. Mine and Man-Houf Computations and Strip Cluster Composition (Sample Problem)

I SITUATION

Desired Density

IOE Representative Cluster

AT a. 1

AT a. 1

Apers Frag b. 4

Apers Frag b. 2

Apers Blast c. 8

Apers Blast c. 2

Meters of Front 200

Note 1. If using paces as the unit of measurement, adjust the density by multiplying by 0.75. (Round each figure obtained up to the next whole number.) Then convert the front to paces by multiplying the front, in meters, by 1.34.

Example: Desired density of mines/meter of front is 1—4—8.

Desired density using paces Desired front using paces

1 x .75 = round up to 1 200 x 1.34 = 268 paces

4 x .75 = 3

8 x .75 = 6

Table 3-2. Mine and Man-Hour Computations and Strip Cluster Composition (Sample Problem) (Continued)

Adjusted density is 1-3-6

Note 2. If paces are used as the unit of measure, you must use the adjusted density and the front, in paces, in your calculations.

II MINE COMPUTATION

NOTE: This example is computed using meters as unit of measure.

(1) Meters of front divided by 9 equals the approximate number of IOE Clusters.

-2QS = 22.2 (round up to 23) 9

(2) Multiply the number of IOE clusters (line 1) x IOE representative cluster (1—2—2).

a. 23 b. 46 c. 46

(3) Meters of front x desired density, if installing in meters (or paces of front x adjusted density, if installing in paces) = mines in minefield.

a. 200 b. 800 c. 1600

(4) Add line 2 and line 3 (subtotal of mines).

a. 223 b. 846 c. 1646

(5) Compute 10% of line 4 for mine rejections, and strip length variances (round up).

a. 23 b. 85 c. 165

55

56

Table 3—2 Mine and Man-Hour Compulations and Strip Cluster Composition

(Sample Problem) (Continued)

(6) Add line 4 plus line 5 = total mines needed.

a. 246 b. 931 c. 1811

(7) Divide total mines needed (by type) by laying rate figures.

AT : 4 mines/hour/man

APF: 8 mines/hour/man

APB: 16 mines/hour/man

Then take sum of man-hours of all three types and multiply by 1.2 to obtain total installation man-hours (includes marking, siting, and recording).

EXAMPLE:

246 = 62 4

-221= 117 8

1811= 114 16

293 Total

293 x 1.2

352 Total Man-Hours Required* 'This figure is only work time. If working in darkness, multiplying by 1.5.

(8) Add a + b + c of desired (or adjusted) density.

(1 + 4 + 8) = 13

Table 3—2 Mine and Man-Hour Computations and Strip Cluster Compositum


(9) Multiply line 8 by — 5

-2. x — = — = 7.8 (round up to 8) 5 1 5

(10) 3 x AT density (3 x 1 ) = 3

(11) Number of strips (highest from line 9 or 10) = 8.

(12) Desired density x 3 (by type) gives total needed to maintain that density.

AT: 3 x 1 = 3

APF: 3 x 4 = 12

APB: 3 x 8 = 24

(13) Distribute total from line 12, as desired, between lettered strips needed (line 11 ) to get strip cluster composition.

AT

Given IOE 1

1 0 0 1 0 1 0 0

Total ** 3

** same as line 12

IOE

~A

B C D E F G H

APF

2

1

2 1 1 2 1 2 2

12

APB

3 3 3 3 3 3 3 3

24

Total across (max 5)

5

5 5 4 5 5 5 5 5

57

58

Tabic 3—2 Mine and Man-Hour Computations and Strip Cluster Composition

MlNl-FILLD LOGISTIC RULES OF THUMB

(1) Fence Trace Formula for fencing 4 sides (meters) one strand.

12 0 (depth) + 2.0 (front) + 160 meters] x 1.40 = total length of

fence (meters)

(2) If using a two*strand fence, multiply by two to obtain meters of

wire required.

(3) Pickets 4 sides total length of fence (see 1 above) = number of

pickets required.

(4) Mme signs The number of signs (4 sides of minefield fenced)

equals the number of pickets.

(5) Engr tape Comes 170 (M)/roll. Used for

(a) Boundaries

fb) Strip centerlines (incl I0E short strips)

(c) Lanes

(d) Gaps

fe) Tripwire safety lines

(6) Sandbags (Avg 3/Cluster) (Used for removal of spoil.)


15

Step 1. Number of IOE clusters x 3.

Step 2. Number of lettered strips x answer obtained in Step 1.

Table 3—2 Mme and Man-Hour Computations and Strip Cluster Composition (Sample Problem) (Continued)

TYPE MINE

M15

M19

M21

M14

M16A1

M18A1

M24

M25

Step 3. 3 x answer obtained in Step 2.

Step 4. Add answer from Step 1 and Step 3.

(7) 2" x 2" x 12" wood stakes. Used:

(a) Right and left end points of mine strips

(b) Each turning point

(c) Beginning and end points of IOE short strips

Table 3—3. Mine-Carrying Capacity of Military Vehicle

2'A T CGO

2'A T DMP

5 T DMP

VA T TRL

103

126

224

10.260

448

1,165

1,260

12,000

56

80

160

4,320

320

480

900

6,720

90

196

192

6,480

672

1,260

1,440

9,216

61

74

132

6,120

264

700

774

7,200

Note. Figures shown are for crated mines only.

59

60

3-5. MINEFIELD MARKING

a Marking Location of Minefield. Minefields are marked (normally fenced) according to the tactical situation to protect friendly personnel from inadvertently entering a minefield. Marking usually consists of a standard two—strand fence with signs indicating mines. Marking is also used to mark lanes or gaps in a minefield. See figures 3—7, 3—8, and 3—9. The U.S. minefield marking set contains components for marking a safe lane 400 meters through a minefield. WAIST HIGH

b Marking and Rcjerencmg Mine Strips. The beginning and end of each mine strip and all turning points in the strip are marked with wooden stakes or pickets driven flush with the ground. When available, nails should be driven into each stake to enable the metallic mine detector to find the stake. Beginning and end points are identified with alphmeric characters (i.e. A1 and A2, B1 and B2, etc.) for identification purposes on the recording form.

Figure 3—7 Minefield marking fence

^ RED SIGN ^ WHITE LETTERS 3"DI A

vV

>

RED SIGN YELLOW STRIPE (REAR) RED SIGN YELLOW LETTERS

Figure 3—8 Standard marking signs

3-6. ORGANIZATION OF MINELAYING UNIT

a Platoon Organization. The organization and duties of members are listed in table 3—4.

b. Safety See paragraph 3—14. c. Camouflage Camouflage discipline must be strictly enforced

(i.e., dispersion of men, vehicles, mine dumps). d Mine Dumps. Mine dumps should be located no closer than 150m

to each other.

62

ilNEFIELO 3 M w

WiNEFlftD

>5 m

(LIGHTS GREEN)

WH TE RED RED (LIGHTS WHITE)

RED

RED

WHITE'

(LIGHTS GREEN) RED

"WHITE'

ENTRANCE RED

—►] 60 cm (24)

20 cm (S')

Figure 3—9. Standard lane markings

Table 3—4. Organization of the Mine Laying Party

Personnel

Supervisory personnel

Siting party

Marking party

Recording party

1st laying party

2nd laying party

3rd laying

Total

Officer NCO EM Equipment

1 1 Officer: Map, lensatic compass, notebook, and minefield record forms.

1 3

1 2

1 2

NCO: Map, notebook, and lensatic compass.

Stakes or pickets, sledges, hammers, tracing tape on reels, and nails to peg tape.

Barbed wire on reels, marking signs, lane signs, wire cutters, gloves, sledges, pickets.

Sketching equipment, lensatic compass, minefield record forms, map, and metric tape.

1 6 to 8

1 6 to 8

Notebook for squad leader,

picks, shovels, and sandbags.

Same as 1st laying party.

6 to 8 Same as 1st laying party.

25 to 31

NOTE: Organization may vary depending on terrain, men, and materials available and the proximity of the enemy.

64

Section III. REPORTING AND RECORDING

3-7. MINEFIELD REPORTS

A minefield report is any message or communication, either oral or written, concerning either friendly or enemy mining activities. Reports of friendly minefields are classified and will be transmitted by some secure means.

a Mandatory Minefield Reports ( 1 ) Report of intention to lay ( table 3—5) (2) Report of initiation of laying (3) Report of completion of laying <table 3—6)

b Additional Reports (submit as needed). ( 1 ) Progress reports (2) Report of transfer (3) Report of change (4) Enemy minefield report (table 3— 7)

3-8. MINEFIELD RECORDS

a DA Form 1355. This form is used to record all minefields except the hasty protective minefield. DA Form 1355 consists of a single printed sheet. The front consists of an upper half for tabular data and a lower half for a scale sketch of the field. On the reverse side are instructions for completing the DA Form 1355 and a form for computing the number of mines. When completed, the DA Form 1355 is classified SECRET. When used for training purposes, the word SECRET must be crossed out and the word SPECIMEN printed on the form in each place the word SECRET appears. (See figs. 3—10 through 3—12). When properly completed the DA Form 1355 should be clear enough to facilitate minefield removal by other units.

Table 3—5. Report of Intention to Lay w/Example

Explanation Latter designation

(Da

Tactical Objectives (Temporary Security Roadblock or Other).

ALPHA Bridge Work Site Security

Type of Minefield BRAVO Hasty Protective

Estimated number and types of mines and whether surface laid mines or mines with antihandling devices

CHARLIE 10 ea. MISAI No A.H.D.

Location of Minefield by Coordinates

DELTA UT 0976

Location and Width of Minefield Lanes and Gaps

ECHO Rt. 67 No.— So. Approach to Bridge

Estimated Starting and Comple- tion Date/Time/Group

FOXTROT Start 190700 May 74 Completion 190800 May 74

a. First minefield in report. b. Additional minefields in report.

65

66

Table 3—6. Report of Completion of Minefield w/Example

Explanation Letter designation

(Da (2)b (3)b

Changes in Information Sub- mitted in Intention to Lay Report

ALPHA None

Total Number and type of AT and Apers Mines Laid

BRAVO Ml 5-299 M26-865 Ml 4-601

Date and Time of Completion CHARLIE 231800 Mar 72

Method by Laying Mines (Buried, by Hand, by Machine)

DELTA Buried by Hand

Details of Lanes and Gaps Including Their Marking.

ECHO WD1 wire on AZ. 270° Ent

& Ex marked w/2U pickets

Details of Perimeter Marking FOXTROT Standard fence

'Overlay Showing Peri- meter, Lanes, and Gaps

GOLF N/A

Laying Unit and 'Signature of Individual Authorizing Laying of the Field.

HOTEL 2d Pit, Co "A", 546th Engr Bn (C)

a. First minefield in report. b. Additional minefields in report. *N/A if transmitted by electrical means.,

Table 3— 7. Report of Enemy Minefield

Explmtlon ctailgnttnn

I2)b* (4)b*

Map Shaet(i) Daalpiatlon ALPHA

Data and Tima of Col lec- tion of Information

BRAVO

Type of Minefield (AT, Apera)

CHARLIE

Coordinates of Minefield Extrametiae

DELTA

Depth of Minefield ECHO

Enemy Weapons or Surveillance

FOXTROT

Estimated Time to Clear Minefield

GOLF

Estimated Material and Equipment required to Clear Minefield

HOTEL

Routes for Bypeaung the Minefield, if any

INDIA

Coordinates of Lane Entry JULIETT

Coordinates of Lane Exit KILO

Width of Lanes (Matara) C*

LIMA

Other, Such es Type of Mines New Mines or Boobytraps

ZULU

* NOTES' a. First minefield in report. b. Additional minefields in report. c. Additional lanes or/and gaps are reported under e

alphabetical listing.

67

68

b. DA Form 1355—1—R. Hasty Protective Minefield Record. The purpose of the Hasty Protective Minefield Record form is to insure the proper recording of any hasty protective minefields laid by detached or isolated units. The form is issued down to and including platoons. It does not replace the current minefield record, DA Form 1355. The Hasty Protective Minefield Record is unclassified as long as the minefield is temporary in nature. However, when the field is declared a deliberate protective field or incorporated into a larger field, it must be classified SECRET and the information transferred to the DA Form 1355. The reverse side of the Hasty Protective Minefield Record (DA Form 1355—1—R) consists of full instructions to the recorder and an example of a recorded minefield.

c. Enemy Minefield Record. The standard DA Form 1355 is used when preparing a record of an enemy field. The record should include a full description of the marking and a sketch or overlay showing location and other information. The record must be marked at the top with the words ENEMY MINEFIELD.

Section IV. REMOVAL OF MINES

3-9. CLEARING MINED AREAS

a. Detection Methods. (1) Visual. (2) Probing. (3) Dogs. (4) Mine Detectors. Both types of detectors, metallic and

nonmetallic, may give signals when items other than mines are detected. Experience in operating each type enables the user to recognize the characteristics of the signal to be expected from each type mine. Since this is a very exacting task, no individual should be permitted to operate a detector for more than 20 minutes at a time.

b. Mine Removal The following methods are used to remove or neutralize mines. These are listed in relative order of use. Where possible, hand neutralization will be avoided.

(1) Explosives. (2) Rope and hooks. (3) Mechanical means. (4) Hand neutralization.

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Figure 3-10b. Standard detailed minefield record (DA Form 1355) (bottom half, front).

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SCMiP 0 •• »»NE ^ '„Ai. Tí m ZTí2&TT¡7

Figure 3-1 la Record oj point minefield with minimum information (top half, front).

:=î:: WARNING: THIS MINEFIELD MAY HAVE BEEN ALTERED BY ENEMY. USE CAUTION WHEN CLEARING

0*

d°

H

* CITY HALL

TMOOTSVI LLC PT3«»lV/tV8 FT SUZliH-i-

V. V.- i.4 FT 38

ROUTS “/o

PT39s^lzn

u FT393

gouf 1 JI_NOTE: ' 0 : TU, jf i I THE WORD SPECIMEN^ MUST BE PRINTED

i 1 « KH«tOM ON THE FORM WHEN THE RECORD IS USED i I i I FOR TRAINING

JAr: 1355 - kM ••••Mw4l

Figure 3-11 b. Record of point minefield with minimum information (bottom half, front).

MINIFIELD ItCOID

•- C-S. t *X( INF.) POtHT 6711** MfKHCH 1975

3 F>LTj Co“**, TkL&tfTVILLE. i:34.*44 4*7x444 A>ARcw ms 2/.T- JEW SöT Ate. DAVIS 307-2»-/W3 7Ä/

AfcFep£A/Cg. ST^Xig.

i^SMAPf-D PICKET EJi-l^»hja 9u«AP5 u#"T* aA«R. TAP« undM_r7/^ VT 7627777/

MICKCFK^CM OtiiD/WC EAST eiDC. ROAO IMTERÆCTION

Rett'S

09fiUl I. ALL MM3 • EÇUtP**.0 U/iTH O^TRJCCARS,

i. AU MIMES ARE WATER /RESISTANT TREATED

1 ALL SAFETIES BORIEO -5 METER sotTU OF REFERENCE STAKE..

4 AMERASE DEPTH OF STREAM IS ONE METER.

I ARROWS SHOW DIRECTION AZIMUTHS WERE TAKEN.

A. MINES ARE NUMBERED IN SEOUEA/CE THE/ WERE INSTALLED-

Z CLUTTERS On 177TB NONI 29

Figure 3-12a Record of mines implaced in a ford deeper than 0.6 meters (top half, front).

rvAJ&H WJ . Jk-J (AJOODS

\LL

ï--

CJÆH-^

% Ti s/f

-í P^L

eA= s£^ KE'

T«

nK»a

S5 j.»*1 (U&: ¡»r írS^ NOTE: sí«

ICK=I0” THE WORD "SPECIMEN" MUST X — BE PRINTED ON THE FORM AND

THE WORD "SECRET" CROSSED OUT WHEN THE RECORD IS J \ n rfl/hir USED FOR TRAINING. SPfrM.f, 1G'* -£***i¿¿Á¿¡A

Figure 3-12b Record of mines implaced in a ford deeper than 0.6 meters

3-10. HASTY BREACH OPERATIONS

A hasty breach operation is performed when the tactical situation requires maintaining the momentum of an attack. It will result in a safe lane through a mined area. Two methods of hasty breaching are:

a. Bangalore Torpedo Train. Two—inch diameter by 1.5—meter—long sections. Pushed into obstacle by hand or propelled by rocket motor. Clears a narrow footpath. For detailed information see TM 9—1375—213—12.

b. Demolition Kit Projected Charge Ml57. Approximately 7 inches high. 12 inches wide, and 400 feet long. Weight - 11,000 pounds. Pushed or towed by medium tanks. Detonated by impact fuze. In most soils, it creates a crater approximately 320 feet long, 12 to 16 feet wide, and 3 to 5 feet in depth. For detailed information see TM 9-1375—204—10.

3-11. DELIBERATE BREACH OPERATIONS

Deliberate breach operations are carried out by manual methods with mine detectors and/or probes (fig. 3—13 and table 3—8).

)S m INIiaVAl ItrwKN MlMlftS

Figure 3—13. Deliberate, manual, minefield breaching party. 75

76

Table 3—8. Platoon Organization and Equipment for Manual Breaching

Personnel Officer NCO EM Equipment

Officer in Charge

Platoon Sergeant

No. 1 Breaching Party



Support Party 10

Totals 31

Lensatic compass, map, radio, and individual weapon.

Same as OIC, except without radio.

Two portable detectors, two probes, mine markers, marking tape or wire on reels, safety pines, clips, smooth wiresdB" lengths) %-lb blocks of explosives, blasting caps, detonating cords, safety fuze, fuze lighters, crimpers, and portable radio.

Same as No. 1 breaching party.

Same as No. 1 breaching party.

Same as No. 1 party, plus sledges or mauls, hammers, pliers, wire cutters, 2" by 4" stakes at least 6' long, individual weapons, litters, lane-marking signs, gauntlets, barbed wire, stakes, and pickets.

3—12. AREA CLEARING OPERATIONS

a. Manual method with mine detectors and/or probes (fig. 3—14 and table 3-9).

b Friendly fields. By use of minefield record. c. Route clearance (fig. 3—15). d. Helicopter L.Z. clearance (fig. 3—16). e Average breaching/clearing time and material requirements (table

3-10).

THE 25 - METER INTERVAL BETWEEN DETECTOR PARTIES PREVENTS ELECTRICAL INTERFERENCE BETWEEN DETECTORS AND HELPS TO REDUCE CASUALTIES FROM MINES

1. 3. 6. 7 OITECTOJ--''

OPfRATOtS 3

6 1*4, &

NCO TAPE

!, 4, 6, 8 MARKERS AND

TAPE LAYERS

10, 11

DEMOLITION

MEN

Figure 3-14. Clearing party using electronic detectors.

78

Table 3—9. Platoon Organization and Equipment for Manual Clearing

Pwvonnd

Officer in Charge

No. 1 Clearing Party



Control Party

Totals

Offi NCO EM Equipment

Map, lensatic compass, portable radio, and all avaialble information on mines in area.

Mine probes, tracing tape on reels, mine markers, grapnels, rope, or wire in 50—meters lengths, 18—in. lengths of 10— and 16—gauge wire, demolition equipment, shovels or entrenching tools, and portable radios.

Same as No. 1 clearing party

Same as No. 1 clearing party.

Map, lensatic compass, portable radio (2 preferably, 1 for platoon and for company net).

3-13. TACTICAL EMPLOYMENT OF CLAYMORE MINE M18A1

a. General. The CLAYMORE is primarily a defensive weapon which may be directionally sighted to provide fragmentation over a specific area. The major advantage of the CLAYMORE is that it is adaptable to controlled detonation and does not rely solely upon chance detonation by the enemy. The CLAYMORE is particularly suitable for use in the hasty protective minefield.

FLANK

SECURITY

X -» -SO- 100 M —

FLANK

SECURITY

PROOF ROLLING

TWO LOADED ANO SANO '

BAGGED 5—TON DUMP

TRUCKS BACKING ,

ALONG ROUTE /

X

FLANK

SECURITY

X

FLANK

SECURITY

X <4—50- 100 M

FLANK

SECURITY

SPEED

3-5 MPH

DIRECTION

OF SWEEP

NCO

A S

RTO

DETECTOR PROBER

DEMO A

ôt RTO

S DETECTOR S PROBER S DEMO

A NCO

*—J RTO

X

FLANK

SECURITY

100 M FLANK

SECURITY

100 M

30 M

X

FLANK

SECURITY

30 M

50 M

X

FLANK

SECURITY

50 M l

A PC OR GUN TRUCK

100M-»» X

FLANK

SECURITY

END: S—SOLDIER

X—SECURITY

PERSONNEL

A —NCOIC

rt-orc

Figure 3—15. Typical sweep team formation.

79

80

HELIPORT CLEARING METHOD

7 III

m 3 m N. ^

3 m

I = PHASE I CLEARANCE. TWO 10 METER WIDE DIAGONALS AND

A 6 METER WIDE PERIMETER STRIP.

II = PHASE II CLEARANCE. FIVE HELICOPTER PADS.

Note Tha lin of aid dteanot bttwMn landing pads

dmuM In donrniimd by oootdlnation with

dn nlrton unit ntikh will un tin Miport.

Ml = PHASE III CLEARANCE. REMAINING AREA.

Table 3—10. Minefield Average Breaching/Clearing Time and Material Requirements

Method Width of cleared lane (in meters)

Man-hours req'd per 100 meters

Remarks

MANUAL

Location by probing 1 (footpath) 16-22 See note.

Removal by rope or explosives

1 (footpath) 38-44 See note.

Location by detector, assisted by probing

8 (one-way vehicle lane)

27-33 See note.

Removal by rope or explosives

8 (one-way vehicle lane)

220-247 See note.

ÊXPLOSIVE^

Demolition snake Ml57 Diamond Lil)

4.0—6.0 6-8*

6 to 8 man

hours to assemble

Bangalore torpedo 1 (footpath) 3.5—4.5 See note.

NOTE: Based upon average conditions of visibility and moderate enemy activity and normal U.S. countermeasures; i.e., screening of enemy observation and counter-battery fires against hostile artillery or other weapons covering the field.

'Per 90 meters (set is only 90 meters long.)

81

82

b. Defensive Uses. (1) To cover the range between maximum hand grenade throwing

distance and the minimum safe distance of mortar and artillery supporting fire.

(2) To supplement other minefields when equipped with tripwires. (3) To fill the dead space of the final protective fires of automatic

weapons in defensive positions. (4) To provide security of outposts, command posts, halted columns,

etc. (5) To cover roadblocks and obstacles. (6) To cover retrograde operations.

c Offensive Uses (ambushes). (1) Laterally along the killing zone. (2) At the front and rear of the killing zone. (3) Laterally along the killing zone on the far side of the killing zone

from the ambush element. This method is particularly effective in countering enemy immediate action that includes maneuver or withdrawal from the killing zone. Care must be taken to insure the ambush element is protected from fragmentation.

d. Safe Distances. See table 3—1.

3-14. SAFETY PRECAUTIONS

a. Personnel in a minefield will: (1) Remain dispersed. (2) Not run. (3) Move only in cleared areas. (4) Move to assist injured personnel only when told to do so by unit

officers or noncommissioned officers. b. All areas or facilities are suspect and are carefully investigated. c. Cleared areas are distinctly marked. d. All mines are considered to be equipped with antihandling devices

until proven otherwise. Never uncover a mine until the ground on top has been thoroughly checked for antilift devices.

e. Hand removal of mines is undertaken only when no other means of disposal is feasible (i.e., minefield being cleared at night to keep enemy from finding out it is being cleared).

f. All precautions for handling explosives are observed when handling mines, fuzes, and firing devices.

g Mines that are removed are completely separated from fuzes and firing devices and stored separately.

h. Rapid means of communication should be maintained to insure maixmum control and prompt evacuation of any wounded personnel. Medical aid personnel should be close at hand to accomplish any needed first aid.

I. All minefields are reported and recorded no matter what the size or type of hardware used. One mine, placed in front of an outpost, is a minefield.

83

84

CHAPTER 4

FIELD FORTIFICATIONS

Section I. GENERAL DATA

4-1. PRIORITY OF TASKS

The tasks involved in organizing a defensive position are carried out concurrently, but the situation may require that priority be attached to some. The unit commander specifies the sequence for the preparation of the positions with as many tasks being accomplished simultaneously as possible. The normal sequence of tasks is:

a. Establish security. t>. Position weapons. c. Clear fields of fire, remove objects, mask observation, and determine

ranges to probable target locations. d. Prepare weapons emplacements and individual positions to include

overhead cover and camouflage. e. Provide for signal communications and observation systems. f. Emplace obstacles. g. Prepare routes for movement, supply, and evacuation. h Improve primary positions to include protection from CBR attack. I. Prepare deceptive installations in accordance with plans of higher

headquarters.

4-2. CLEARING FIELDS OF FIRE

a. Principles. (1 ) Excess or careless clearing will disclose firing positions. (2) In areas organized for close defense, clearing should start near the

position and work forward for at least 100 meters or to the maximum effective range of the weapon if time permits.

(3) A thin natural screen of vegetation should be left to hide defensive positions.

b. Procedure ( 1 ) Remove the lower branches of large scattered trees in sparsely

wooded areas. (2) Restrict work to thinning the undergrowth and removing the

lower branches of large trees when clearing in heavy woods. Clear narrow lanes of fire for automatic weapons.

(3) Thin or remove dense brush since it is never a suitable obstacle and obstructs the field of fire.

(4) Cut weeds when they obstruct the view from firing positions. (5) Remove felled limbs, brush, and weeds to areas where they cannot

be used to conceal enemy movements or disclose your position. (6) Do only a limited amount of clearing at one time.

Overcommitting the unit may result in a field of fire improperly cleared. This would benefit the enemy.

(7) Cut or burn grain, hay, and tall weeds. c Man-hours Required.

(1) Approximately 5 man-hours per hundred square meters are required to clear average growth.

(2) Add 50 percent if working in darkness.

Section II. TYPES OF FORTIFICATIONS

4-3. EMPLACEMENTS

a Requirements Emplacements should be constructed to: (1) Permit each individual to accomplish assigned fire missions. (2) Be simply and easily constructed. (3) Provide maximum protection with minimum time and labor. (4) Be camouflaged and concealed. (5) Provide protection against mechanized attack. (6) Provide protection against nuclear attack.

b. Types and Dimensions - Frontal Parapet Fighting Positions (figures 4—1 through 4—7)

85

86

¿'S

& i-':

F6ET ARE PLACED MORE THAN SHOULDER WIDTH APART

Figure 4-1. Measurements, one-man emplacement

DIRECTION OF ATTACK

I M-16 RIFLE LENGTH

RIFLE LENGTH WITH BAYONE ATTACHED

i 45

BERM I BAYONET LENGTH

2 BAYONET LENGTHS EMPLACEMENT

, M-16 RIFLE

LENGTH 1« s 2 BAYONET I IFNGTHS LENGTHS

Figure 4-2. One-man emplacement (vertical view)

RIGHT SECTOR

OF FIRE LIMITS

-■wirT'C 'i&Wîÿ;

RANGE CARO LEFT SECTOR OF FIRE LIMITS

-AIIX

A' HEIGHT

OF SOLDIER

flL> MIN

3

SEE NOTE 1 s£E NOTE SECTOR OF

FIRE LIMIT STAKES

COVER WITH MIN

18“ SOIL AND CAMOUFLAGE

BIG ENOUGH TO GET UNDER &

* «.DRAINAGE SUMP FILL WITH ROCK

OR BRUSH

CONSTRUCTION TIME USING

ENTRENCHING TOOLS - 8 HOURS

NOTES. 1. END OF PARAPET MUST BE AT LEAST 4" HIGHER THAN MUZZLE OF

WEAPON WHEN IN FIRING POSITION.

2. REAR OF PARAPET MUST BE HIGH ENOUGH TO PROTECT A MAN’S HEAD.

Figure 4-3. One-man emplacement (cross-sectional view).

LEFT SECTOR OF

FIRE LIMIT STAKES

GRENADE SUMP

12” OPENING 18” DEEP 45° ANGLE

«er .,,x

1 •J?- ^Tr mz "w (T^ Ä-f 3Ç-

HIT AH PLACID MORI THAN SHOULDIB WIDTH APART

Figure 4-4. Measurements, two-man emplacement.

87

m. isaH m, ¡es

^4y

IE KM

2 M-U RlrLf ■ LENGTHS*

1 M-16 IlflE LENGTH WITH BAYONET ATTACHED

EMPLACEMENT

1 M-U KIELE LENGTH

I BAYONET LENGTH

2 BAYONET LENGTHS

L

Figure 4—5. Two—man emplacement (vertical view).

RIGHT SECTOR OF RANGE CARDS-,

FIRE L MITS

mi SEE NOTE 1

M I-IHEIQHTî^ \f\ I i I OF SOLDIER

set

7 LEFT SECTOR OF

FIRE LIMIT STAKES

TO GET UNDER

I u MIN

COVER WITH MIN 18” SOIL & CAMOUFLAGE

LEFT SECTOR OF

FIRE LIMITS

RIGHT SECTOR OF FIRE LIMIT STAKES

COVER WITH MIN 16” SOIL AND

CAMOUFLAGE

GRENADE SUMP 12” OPENING 18” DEEP 45° ANGLE

DRAINAGE SUMP FILL WITH ROCK OR BRUSH CONSTRUCTION TIME USING

ENTRENCHING TOOLS - 8 HOURS

NOTES: 1. END OF PARAPET MUST BE AT LEAST 4” HIGHER THAN MUZZLE OF

WEAPON WHEN IN FIRING POSITION.

2. REAR OF PARAPET MUST BE HIGH ENOUGH TO PROTECT A MAN'S HEAD.

Figure 4—6. Two—man emplacement (cross-sectional view).

VA

'Æ ///>

as

Figure 4— 7. Occupied one-man emplacement.

c. Foxhole Digger Explosive Kit. This item greatly increases a unit's capability to create emplacements with a minimum of time and labor. See figure 4—8.

( 1 ) Characteristics (a) Case.

Material- Plastic Shape—Tubular Size—7.38 x 2.28 in.

(b) Shaped charge. Material—Plastic and copper Shape-Tubular Size--7.37 x 2.0

89

90

(c) Cratering charge. Material—Pressed explosive inside sleeve Shape—Tubular Size—8.21 x 1.0 in.

(d) Fuze. Material—Steel Shape—Tubular Size—4.25 x 0.56 in.

(e) Basis of issue. Individual combat soldier

tMACCD DllAT FUZI CMAIOC

X STAtlllTY ioov

ft«™0 AJ "b

A

CONTAINII JD

ST i TAPI pO-J

OtATIBINO CHABOI

(I) BIMOVI ALL PABTS PBOM INSIDE CONTAINEB (J) LEAVE CAP OFF

Figure 4-8. Foxhole digger explosive kit.

Type of emplacement or dêtter

Total construction time in man hour* for construction with D-handte thoveb and ordinary carpentry tools

Revetment mataríais for cover support

only

Comí-

metal constr.

Sized lumber

Completa

metal constr.

Sized lumber

materials

Improved crater

Skirmishers trencn

Prone emplacement

Open one man foxhole

Open one man foxhole with offset

One man foxhole with half cover

One man foxhole with half cover and offset

Open two man foxhole

Deepened two man foxhole

Two man foxhole with half cover

Two man foxhole with half cover and two offsets

Two man foxhole with half cover and adjoining shelter

Open fighting trench 125* length)

Fighting trench with full cover 125' length)

N/A

N/A

N/A

N/A

9.0

2.5

10.0

N/A

N/A

4.0

20.0

11.0

N/A

27.0

N/A

N/A

N/A

N/A

14.0

3.0

14.0

N/A

N/A

4.0

30.0

17.0

N/A

29.0

N/A

N/A

N/A

3.5

10.0

4.5

12.0

6.0

8.0

8.0

22.0

13.0

28.0

35.0

N/A

N/A

N/A

4.5

16.0

5.5

18.0

8.0

10.0

10.0

35.0

220

32 0

40.0

0.5

0.5

1.5

2.0

N/A

N/A

N/A

3.0

5.0

N/A

N/A

N/A

21.0

N/A

Figure 4-9. Time required to construct individual, crew-served, and artillery weapons emplacements.

C'J O)

Type of emplacement or shelter

Total construction time in man hour« for construction with D-hendle rfioveis and ordinary carpentry tools

materials for cover support

only

Corru-

metal constr.

Sized lumber constr.

Complete

Corru- gated

metal constr.

Sized lumber

ment materials

Open automatic rifle emplacement

Automatic rifle emplacement with 18" of cover

Open horseshoe type M60 machmegun emplacement

Open 2 one-man foxhole type light machmegun emplacement

Horseshoe type light machmegun emplacement with full cover

2 one-man foxhole It. machmegun type emplacement with % cover and adjoining shelter

Circular type .50 cal machmegun emplacement

Pit type emplacement for recoilless weapons

81-mm mortar emplacement

4.2-inch mortar emplacement

Recoilless rifle position (mounted) '.

Recoilless rifle position (dismounted)

105-mm howitzer emplacement

155-mm howitzer emplacement

N/A

40

N/A

N/A

9.0

15.0

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

5.0

N/A

N/A

11 0

22.0

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

7.0

80

8.0

6.0

11.0

19.0

14.5

5.0

12.0

29.0

N/A

N/A

N/A

N/A

8.0

7.0

10.0

7.0

14.0

280

165

60

N/A

N/A

N/A

N/A

N/A

N/A

4.0

N/A

4.0

4.0

N/A

N/A

10.0

3.0

N/A

N/A

30.0

17.0

100.0

170.0

Figure 4-9. Time required to construct individual, crew-served, and artillery weapons emplacements (Con’t).

(2) EJfect. (a) The shaped charge will penetrate soil, depending on the density,

to depths varying from 50 to 85 cm. (19.7 to 33.5 In.), forming a tapered hole 6 cm. (2.4 In.) in diameter at the top and 1.5 cm. (0.6 In.) at the bottom.

(b) The cratering charge will form a crater In soil about 107 cm (42 in.) In diameter and about 80 cm (31.5 In.) deep.

4-4. REVETMENTS

a. Retaining Walt Type Used In relatively unstable soils. The horizontal layers of the walls are tied together so that the wall acts as a structural unit. Revetments may be constructed of sandbags, sod blocks, and other expedients. The methods of construction are as follows:

(1) Sandbags (fig 4—10)

^L-SECTTQN- ÊLEVATION-

CHOKES & SIDE SEAMS IN

STRETCH! HEADERS

jlEVATION—=r

JOINTS BROKEN Figure 4-10. Sandbag retaining wall.

93

(a) FMI three—fourths full. (b) Stabilize bags by filling with 1 part cement to 10 parts dry

earth. In a sand—gravel mixture, increase ratio to 1 to 6. (c) Tuck in bottom corner of bags after filling. (d) Place all bags on bottom row as headers (fig. 4—10).

(e) With stabilized sandbags, the foundation should De about 15 centimeters below floor level.

(f) Alternate intermediate rows as headers and stretchers. (g) Slope the wall toward revetted face at slope of 1 to 4. (h) Place bags perpendicular to slope. (i) Place about 800 sandbags per 25 square meters of revetted

surface. (2) Sod blocks (thick sod with good roots). Cut Sod blocks into 20

by 45 centimeter sections and lay flat, using alternate stretcher—method as with sandbags. Lay sod grass-to-grass and soil—to—soil except for the top layer which is placed with grass upward for camouflage. Drive two wooden pegs through each section of every layer as it is completed. Lay sod revetment at a slope of 1 to 3.

(3) Expedients, such as ice blocks, may be used in cold weather. Stack them in the same way as sandbags or sod, and run water over them in order to bind them by freezing. Another expedient is earth-filled packing cases or ammunition boxes which are placed in position and nailed to the layer below. The boxes are then filled with earth or rock. In wooded areas, small timber may be used as revetting material.

b. Facing Type. Serves mainly to protect surfaces from weather and damage caused by occupation. It consists of facing materiel, the top of which is set below ground level so that the revetting material is not damaged by tanks crossing the emplacement.

(1) Types of material Materials used in facing may be brushwood hurdles, continuous brush, pole and dimensional timbers, corrugated metal, or burlap and chicken wire. Construction methods are described in paragraph 4—4—b—(3) below.

(2) Methods of support (a) Timber frames of dimensioned timber are built to fit the

bottom and sides of the position and hold the facing material apart. This insures that the excavated width remains stable.

(b) Pickets are driven into the ground on the position side of the- facing material and held tightly against the facing by bracing the pickets apart or fastening their tops to stakes or holdfasts (fig. 4—11 ).

STAKES OR HOLDFASTS PLACED HERE

t • ft .

u7 Ei

'ir

wm ‘■m- «

í.1 ¿ ■i,;-. ■

D, IS EQUAL TO OR GREATER THAN H D2 IS EQUAL TO H + 61 cm

Figure 4—11 Method of anchoring retaining wall posts/pickets.

(3) Methods of constructing facing type revetments (a) The size of pickets depends upon the soil type and the kind of

facing material, but timber pickets should not be smaller than 8.0 centimeters in diameter. Maximum spacing between pickets should be 1.75 meters. U—shaped pickets are excellent for revetting. Pickets are driven at least 0.5 meters into the floor of the position. Where the pickets are anchored at the top, proceed as shown in figure 4—11.

95

96

(b) A brushwood hurdle isa woven revetment unit, usually 1.75 to 2.0 meters long and of required height.

(c) The pole revetment is similar to the continuous brush revetment, except that a layer of small horizontal round poles cut to wall length is used. If available, boards or planks are used.

(d) Corrugated metal sheets or pierced steel planks are strong, durable, and rapidly installed. They may be used for any height or length of revetment. Smear metal surfaces with mud to eliminate possible reflection of thermal radiation and to aid camouflage.

4-5. BUNKERS

a In bunker design two basic criteria must be considered: (1 ) The purpose of the bunker (CP, firing positions, etc.). (2) Weapons from which protection is desired (small arms, mortars,

bombs, etc.). b. A bunker should be constructed wholly or partly below ground level.

If above ground level, columns or posts should extend belwo ground level for anchoring.

c The protective cover and roof of a bunker should be designed so that it moves freely but is rigid enough to displace as a unit. It must also be able to absorb the shock of an exploding shell. To accomplish this, sandwich type construction is used. See figures 4—12 and 4—13. The burster course and roof structure must be both rigid and resilient and the middle layer be porous and capable of cushioning against shock.

d In timber construction, notching of lumber should be avoided. e. All bunkers should have overhead cover of at least 18 inches in order

to defeat an 81-mm mortar surface burst.

4-6. SHELTERS

The most effective shelters are underground cut and cover. Typical shelters, including an air transportable recoverable shelter, are shown in figures 4—14 thru 4—17 and table 4—1. See FM 5—15 for other, more permanent types.

.151

cm

.

Non, WALL TIMMRS ARE 15c* x 15c*

15c* (APPROX) OVER HANG

- CAMOUFLAGE LATIR

-RUIITIR LAYER

-UNCOMPACfED SOIL LATER L <vC*

1 140c* (APPROX)

Figure 4-12a Bunker (interior view)

454 cm

121 cm 242 cm •— 91 cm 5 cm

•—91 cm 182 cm

15 cm

■ ROOF OUTLINE

Figure 4-I2b. Bunker (plan view).

97

181

cm

r|l

g

|5c*

45c*

98

Scm OF CAMOUFLAGE 30cm OF 15cm TO 18cm ROCK

rDUST-PROOF LAYER

30cm OF UNCOMPACTED SOIL

cur, ..„r » » IJ_I S LAYERS SAND BAGS 5 x 30cm

25g BOARDS

DETAIL

ENTRANCE

WATER-PROOF LAYER

^ 60 cm

E f^= o * ñ " FIRING PORT

90 cm f

j I

Figure 4-12c Bunker

ITEM DESCRIPTION !NO.PCS|

ROOF

SIDE WALLS

ENTRANCE WALL

FIRING PORT AND

ENTRANCE DOOR

FRONT AND REAR

WALLS

FIRING PORT AND RETAINING WALL

SIDE POST

SIDE POST

5 CM X 30 CM X 2.11 M LONG 5 CM X 30 CM X 4.54 M LONG - WOOD

15 CM X 15 CM X 2.42 M LONG - WOOD


15 CM X 15 CM X 30 CM LONG - WOOD



15 CM X 15 CM X 2.85 M LONG -WOOD


48 PCS 14 PCS 26 PCS

26 PCS

26 PCS

13 PCS

8 PCS

6 PCS

2 PCS

Figure 4—¡2d Bunker (bill of materials)

LOOSE EARTH CUSHION

LAYER

'WmSŒMÈÊfâ

S CM(BURSTER LAYER)

30 CM

IS•20 CM

30CM 30CM

SECTION

L T 7« DEPTH

OP CUT DEPTH

OP CUT

¿SlUim—rmii... i n. MONT view

Figure 4—IS. Fighting bunker with overhead cover.

99

100

AIR VENT

LJ

■XL

DRAINAGE DITCH

BOARD WALK

CUT-AND-COVER SHELTER IN A HILLSIDE (BAFFLE WALL OF ENTRANCE CAMOUFLAGE OMITTED) SHADED AREA AND BROKEN LINES SHOW CUT-AND-FILL SECTION.

-AIR VENT

BOARD :.Y.: :

WALK

}::y t /

SAN BAGS w r,

DRAINAGE DITCH

CUT-AND-COVER SHELTER IN ACUT BANK SHOWING SAND-BAGGED OUTER WALL. SHADED AREA AND BROKEN LINES SHOW AREA OF CUT-AND-FILL.

Figure 4—14. Cut and cover shelter.

1. SHAPE EXCAVATION A EKECT IUNKEK

1. EXCAVATE WITH EXPlO<IVES

' lACXnu 4. CONSTIUCT «OOP, DIO OOOIWAT ANO OIAINAOE DITCHES

Figure 4—15. Air transportable underground assault bunker (prefab)

BILL OF MATERIALS

4' x 8' x %" PLYWOOD 20 EA

4" x 8" x 14' TIMBERS 13 EA

4" x 4" x 8'TIMBERS 10 EA




2" x 4" x 8' TIMBERS 10 EA

TRIM (METAL EDGING) 190 FT

OPTIONAL

BOLTS (FOR HINGES) 128 EA

WOOD SCREWS (OR # 8 NAILS) 5 LB

PAINT (O. BRAB) 1 GAL

HINGES 16 EA

U- BOLTS W/BEARING PLATES 4 EA

Figure 4—16. Bill of materials (air transportable underground bunker)

102

^CAMOUFLAGE LAYER^-gL

! BURSTER LAYER! -

jl WATE RPRÔOT'LÂYÉ Ri_ l|!R»S«SSasgi^®SS5®8^ . ^CUSHION LAYERgS

1 DüSTPRöOF j '

30 cm

ÎÏSJS 32 ¡SS

THICKNESS 5-5 cm BOARDS OR 7- 2.5 cm BOARDS

LAYER LAMINATED ROOF

ÍÑOTE: ^CUSHION & BURSTER

LAYERS EXTEND

BEYOND EDGES OF SHELTER A

MINIMUM OF 1.5m !%

1 LAMINATED ROOF CONSTRUCTION

Figure 4-17a. Heavy overhead cover (laminated roof construction).

5 cm

30 cm

i,' < / i i". i i í ' ÛQM^/CAMOUFLAGE LAYER

fER ATERPROOF — LAYER ioîcin TOP cUsfllofTiÄVl

30,cm LOWER CUSHjON LAYER

STRINGER ROOF

DUSTPROOF LAYER

NOTE: THE CONSTRUCTION IS SIMILAR TO LAMINATED ROOF CONSTRUCTION WITH THE ADDITION DF-

ID A LOWER CUSHION LAYER 30 cm THICK ON TOP OF THE DUSTPROOF LAYER. THIS LAYER OF UNTAMPED EARTH DOES NOT EXTEND BEYOND THE SIDES OF THE SHELTER.

/

(2) A DISTRIBUTION LAYER CONSISTING 20 cm TIMBERS. THIS LAYER EXTENDS BEYOND EACH SIDE OF THE SHELTER A MINIMUM OF 1.5 METERS AND RESTS ON UNDISTURBED EARTH TO TRANSMIT PART OF THE LOAD OF THE TOP LAYERS TO THE UNDISTURBED EARTH ON EACH SIDE OF THE SHELTER.

Figure 4—17b. Heavy overhead cover (stringer roof construction).

104

Table 4-1. Bill of Materials for One 6' x 8’ Sectional Shelter With Post. Cap and Stringer Construction—Dimensional Lumber

Material List

No. Nomenclature Rough size Quantities

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19

Cap or sill Post Stringer** Spreader Post, door Brace Brace Brace Spreader Spreader Spreader Scab Siding Siding Siding Siding Roll roofing Driftpin Nails

6" x 8" x 8'0" 6" x 6" x 5'10" 6" x 6" x 6'0” 3" x 6" x 5'0" 3" x 6" x 6'6" *3" x 6" x 7'0" *3" x 6" x 6'10" *3" x 6" x B'O" 2" x 6" x 3'3" 2" x 6" x 2'9" 2" x 6" x 2'0" 3" x 6" x 2'0" 3" x RW x B'O" 3" x RW x 6'0" 3" x RW x 4'0" 3" x RW x 3'6" lOOSq ft roll %" x 14" 60d

4 6

16 4 1 1 3 2 3 2 2 2

41‘A SF 36 SF 24 SF 21 SF

6 44 32 lb

‘Allowance for double cut ends of braces is included in overall length as shown under rough size.

’•Laminated wood roof (fig. 4—17—a) may be substituted if desired.

Section III. BARBED WIRE ENTANGLEMENTS

l 4-7. TYPES

Obstacles are classified as either antipersonnel or antivehicular and may be deliberate or expedient.

4-8. PRINCIPLES OF EMPLOYMENT

In order to be effective, obstacles should be: a. Under friendly observation, covered by fire, and protected by

antipersonnel mines, flame mines, and warning devices. b. Concealed from enemy observation by incorporating terrain features

such as reverse slopes, hedges, woods, and fence lines. c. Erected in irregular traces. d. Employed in depth. e. Coordinated with other elements of the defense. f. Tied in with other obstacles. g. Provided with lanes and gaps. h Of no advantage to the enemy.

4-9. CLASSIFICATION OF BARBED WIRE

a. Belt. One entanglement, one fence in depth. b. Band. Two or more belts with no interval between them. The band

may be composed of two or more fences of different types, in which case it would be called a combination band.

c. Zone. Two or more bands or belts in depth with intervals between them.

105

106

4-10. ESTIMATING BARBED WIRE REQUIREMENTS

a. Conventional Deployment., (along FEBA) Rules of Thumb. (1 ) Tactical wire; (front) x (1.25) x (number of belts). (2) Protective wire; (front) x (5) x (number of belts). (3) Supplementary wire.

(a) Forward of FEBA, (front) x (1.25) x (number of belts). (b) Rear of FEBA; (2.5) x (unit depth) x (number of belts).

b. Base Camp Defense (Jig 4-I8Í. (along perimeter) Rules of Thumb.

-y-X-X

X

IX 1 X X TACTlCAlWIRt

X- X- X PROTECTIVE WIRE

=Xc= SUPPLEMENTARY WIRE NOTEi ANGLES OF FINAL PROTECTIVE LINES HAVE SEEN EXPANDED FOR CLARITY OF WIRE EMPLOYMENT

Figure 4-18 Perimeter defense wire

(1) Tactical wire, (mean perimeter) x (1.25) x (number of belts). (2) Protective wire; (perimeter) x (1.10) x (number of belts). (3) Supplementary wire; (mean perimeter) x (1.25) x (number of

belts). c Supply and Labor. For construction estimates of man-hours and

materials, see tables 4—2 and 4—3.

4-11. BARBED WIRE TIES

Various barbed wire ties are shown in figure 4—19.

TOP-EYE TIE INTERMEDIATE-EYE TIE

APRON TIE POST TIE Figure 4—19. Barbed wire ties.

107

108

Table 4—2 Wire and Tape Entanglement Materials

Materials

Barbed wire reel Bobbin Barbed tape dispenser Barbed tape carrying case Standard barbed tape concertina Standard barbed wire concertina Expedient barbed wire concertina General purpose barbed tape obstacle

Hand Vehicular

Screw pickets: Long Medium Short

U—shaped pickets: Extra long Long Medium Short

Wooden pickets: Extra long Long Short

Approx weight,

kg

41.5 3.5—4.0 0.77 14.5 14 25.4 13.5

16 112

4 2.7 1.8

7.25 4.5 2.7 1.8

7.7-10.5 5.4- 7.25 1.4- 2.7

Approx length.

400 30 0.45 300 15.2 15.2 6.1

20 140

1.6 0.81 0.53

2.4 1.5 0.81 0.61

2.13 1.5

0.75

No. carried

by one man

'A

4-6 20 1 1 1 1

2 1

4 6 8

3-4 4 6 8

Approx weight of man-load

kg

21 14.5-24.5 15.5 14.5 14 25 13.5

32 112

16.3 16.3 14.5

21.8-19.0 18.1 16.3 14.5

15.4-20.8 16.3-21.7 11.0-21.7

Table 4—3 Material and Labor Requirements for 300—Meter Sections of Various Barbed Wire Entanglements

Type of entanglement

Double-apron, 4- and 2-pace

Pickets Long

100

Med Short Reels of barbed wire

(a)

200 14-15 dl19)

No. of GPBTO

(f)

No. of concer tinas

Staples

Man- hours

to erect (c)

Kgs of materials per tin m of entanglement

(bl

59 4.6 e(3.5)

Double-apron, 6- and 3-pace

66 132 13-15 d(18) 49 3.6 *(2.6)

High wire (less guy wires)

198 17-19 d(24) 79 5.3 «(4.0)

Low wire, 4- and 2-pace

100 200 11 49 3.6 *(2.8)

4-strand fence 100 5-6 d(7) 20 2.2 *(1.8)

Triple standard concertina

160 3 d(4) 59 317 30 8.2 «(7.3)

General purpose barbed tape obstacle (GPBTO)

'(8) '(1) 2.7

a. Lower number of reels applies when screw pickets are used; higher number when U-shaped pickets are used. Add difference between the two to the higher number when wood pickets are used. b. Average weight when any issue metal pickets are used (1 truckload = 2268 kgs). c. Man-hours are based on the use of screw pickets. Multiply these figures by .67 if experienced troops are being used, and by 1.5 for night work. With the exception of triple standard concertina and GPBTO, multiply these figures by 1.2 when using any type driven picket. d. Number of barbed tape carrying cases required if barbed tape is used in place of barbed wire. e. Kgs of materials required per linear meter of entanglement if barbed tape is used in place of barbed wire and barbed tape concertina is used in place of standard barbed wire concertina. f. Based on vehicular emplaced obstacles installed in triple belts.

109

110

4-12. BARBED STEEL TAPE

Barbed steel tape (fig. 4—20) and barbed tape concertina can be used in the same manner as standard barbed wire and concertina for the construction of barbed wire entanglements. Wrap around ties are used with barbed steel tape similar to the post tie used with barbed wire (fig. 4—19). However, barbed tape must not be pulled tight as it will break when bent sharply. A special dispenser is used to impart a twist to the tape when constructing fences. Recovery of the barbed steel tape for reuse in a standard fence is usually not practical. However, it should be recovered and used to increase the density of other existing entanglements.

4-13. DOUBLE-APRON FENCE, FOUR- AND TWO-PACE

a. Erect from right to left as you face the enemy (fig. 4—21 ). b. Space pickets as follows:

(1) Long pickets are 4 paces apart. (2) Anchor pickets are placed 2 paces from the centerline at midpoint

between center pickets and at each end of fence 4 paces from the first and last center picket.

at

Figure 4—20 Barbed steel tape.

4 PACES 4 PACES

|— 3m —

4 PACES

ENEMY

2 PACES CEMTCR

FENCE 2 PACES

S EAR

15m

ANCHOR PICKETS H.AN

ENEMY ENEMY

LONS PICKET

PACES f 2 PACES 5m »f«-| Sm —• CROSS SECTION

LEGEND:

I - 2-3-4 ETC INDICATES ORDER OP ERECTING WWE

fi?Y&®ce EfCMY EYES OF RCKETS 1

FACE TO RIGHT

ANCHOR PICKET EACH END

OF FENCE

ISOMETRIC VIEW

Figure 4—2!. Double-apron fence.

4-14. DOUBLE-APRON FENCE, SIX-AND THREE-PACE

Erection is the same as in paragraph 4—13 using 6 paces instead of 4 and 3

paces instead of 2.

4-15. CONSTRUCTION PROCEDURE FOR DOUBLE APRON FENCES

a First Operation-Layout and Installation of Pickets (3 Crews).

( 1 ) First crew lays out long pickets.

(2) Second crew lays out short pickets.

(3) Third crew installs all pickets. b Second Operation-Layout and Installation of Wire Men are

organized into two crews of four men each.

(1) First wire, enemy diagonal.

(2) Second wire, enemy tripwire (5-10cm off the ground).

(3) Third and fourth wire, enemy apron.

Ill

112

(4) Fifth, sixth, seventh, eighth, center fence (install from the bottom up).

(5) Ninth wire, friendly diagonal. (6) Tenth and eleventh wire, friendly apron. (7) Twelfth wire, friendly tripwire.

4-16. TRIPLE STANDARD CONCERTINA

a. Erect from right to left as you face the enemy (fig. 4—22). b. Space pickets as follows:

( 1 ) Long pickets are 5 paces apart. (2) Anchor pickets are placed 2 paces from the end of long pickets. (3) Enemy and friendly rows of pickets are 3 feet (0.9m) apart. (4) Friendly picket row is offset from the enemy row.

c. Concertina fences are constructed of barbed wire concertina, barbed tape concertina, or general purpose barbed tape obstacle. There is no differ ence in construction methods for the first two types. Construction methods for the tape obstacle are given in paragraph 4 — 18.

<<<

STEP 1

INSTALL FRONT ROW AND HORIZONTAL WIRE

STEP 2

INSTALL TOP ROW STEP 3 AND RACK TO WIRE

INSTALL TOP ROW AND RACK TO REAR HORIZONTAL WIRE

Figure 4-22. Installing concertinas.

4-17. CONSTRUCTION PROCEDURE - TRIPLE STANDARD CONCERTINA

a. Firn Operation (j Crews). (1) First crew lays out all pickets. (2) Second crew installs all pickets. (3) Third crew lays out concertinas.

(a) Lay one concertina in front of third picket on enemy side.

(h) Lay two concertinas to rear of third picket on friendly side.

(c) Remove binding wire and place on handles.

(d) Repeat same performance every fourth picket thereafter.

b Second Operation (AU Personnel). 11) Install front row concertina and

horizontal wire. (a) Drop concertinas over pickets. (b) Join concertina (fig. 4—23).

w *4

*5

PLACE BOTTOM PORTION OF FIRST COIL OVER PICKET

PLACE BOTH BOTTOM AND TOP PORTION OF SECOND COIL OVER PICKET

PLACE TOP PORTION OF FIRST COIL OVER PICKET

Figure 4-23. Joining concertinas.

113

114

(2) Install rear row concertina and horizontal wire. (3) Install top row concertina and rack to the rear.horizontal wire.

4-18. GENERAL PURPOSE BARBED TAPE OBSTACLE (GPBTO)

a. Description. The GPBTO consists of two concentric helical coils of steel spring tape which are 30 and 24 inches in diameter, respectively (fig. 4—24). The GPBTO is available in a seven-module package containing sufficient tape to erect an obstacle 140 meters long. The obstacle may be emplaced by vehicle, or individual sections may be detached and manually erected. Recovery tools and anchor stakes are included in each container. GPBTO should be employed as a band, 3 belts in depth.

ff

m

Figure 4—24. General purpose barbed tape obstacle

b. Emplacement. GPBTO is erected by anchoring one end of the obstacle to the ground and carrying the package along the desired obstacle path until all the tape is dispensed. Hand emplacement requires one—twentieth the time and vehicular emplacement one—fiftieth the time required to erect concertina. Further instructions are included with each container.

c. Safety. Gloves should NOT be worn when handling the GPBTO. While gloves will reduce minor scratches, they tend to give a false sense of security. The GPBTO barbs are so sharp that they easily penetrate gloves without sufficient resistance to give a warning. Consequently, the hand can be punctured easily when the glove is worn and it can be very difficult to extract the barb from the hand if other barbs are tangled in the glove.

4-19. LOW WIRE FENCE

This is like a 4 and 2 pace double—apron fence, except that medium pickets instead of long pickets are used in the centerline. This results in all apron and diagonal wires being much closer to the ground. The numbers 5, 6, and 7 wires are not used. This obstacle is easily hidden in tall grass or shallow water. For best results, it should be used in depth.

4-20. FOUR-STRAND CATTLE FENCE

This is the four—strand center section of a double-apron fence. In farm country this obstacle blends in with the landscape. If guy wires are used, estimate separately because this material is not included in table 4—3.

a. The working party is divided into two equal groups. The first group lays out long pickets at 3—meter intervals. It begins and ends the section with an anchor picket, including anchor pickets for guys, if needed. The second group installs the pickets.

b. Teams of two or four men are then organized to install wires. In four—man teams, two men carry the reel, and two make ties and tighten the wire. In two—man teams, the wire is unrolled for 5- to 100 meters before ties are made. The wires are installed from the bottom up.

115

116

4-21. TANGLEFOOT

Tanglefoot is used where concealment is needed (fig. 4—25). Use it in a

minimum depth of 9 meters. Place pickets at irregular intervals of from 0.75

to 3 meters. Height of the barbed wire varies from 0.25 to 0.75 meters. Site

this wire in scrub if possible. Use bushes as supports for part of the wire. Use

short pickets in open ground.

c^r

%

F 'S

sí

K—1-4 —í>n¿ ~ PACES o.

W C^—

.25-.75M NOTE: TANGLEFOOT. AS PICTURED. IS DESIGNED TO DISRUPT ENEMY

DURING AN ASSAULT. WHEN USED AS A COUNTER-SAPPER MEASURE THE TANGLEFOOT SHOULD BE STRUNG OUT AT IRREGULAR CRISS-

CROSS PATTERNS SO AS TO CREATE RECTANGLES OR SQUARES OF ABOUT .6 x .6 METERS AT VARYING HEIGHTS OF 10-15 CENTIMETERS. DOING THE ABOVE SHOULD CAUSE THE SAPPER TO HAVE TO RISE OVER THE WIRE EXPOSING HIM TO FIRE.

Figure 4—25. Tanglefoot.

4-22. PORTABLE BARBED WIRE OBSTACLES

a. Standard concertinas are considered portable as they are readily moved.

b The knife rest (fig. 4-26) is a portable wooden or metal frame strung with barbed wire. It is about 4.5 meters long and 1.2 meters high. It must be securely fixed in position.

- * HU

Figure 4—26. Knife rest.

Section IV. EXPEDIENT OBSTACLES

4-23. EXPEDIENT OBSTACLES

See figures 4—27 through 4—34

117

118

Ij-V

■1,V

7H I

, - '/

Figure 4—27 Belt oj imbedded sharpened stakes

J I I I I 1 .1 1 I

Figure 4-28. Caltrop

ENEMY SPOIL

REVETTED

® TRIANGULAR DITCH

REVETTED

ENEMY

4.5 TO 6.0 SPOIL

(2) SIDEHILL CUT

SPOIL

•ï&Mm 2 ,o s™ »V/ —7.Sin niin

HURDLE OBLIQUE TO LINE OF DITCH ENEMY

HURDLE

’TTZVZF^TTTrVTZ

REVETTED

® TRAPEZOIDAL DITCH

Figure 4—29. Trapezoidal ditch

119

120

i -I I

1.8 - 2.4m

— A

1^

3 - 4r

X -ROADWAY

POSITION OF OBSTACLE

V

7.5

4.5 m

. ROADWAY-

POSITION OF OBSTICLE

EMPLOYMENT OF STAGGERED

1.8 - 2.4m HURDLES

(3.25cm LOGS OR 1.45<m LOG)

EMPLOYMENT OF 45cm

LOGS AS HURDLES

WIRE LASHING

60c

LOGS WIRED TOGETHER

GROUND LEVEL

10 - 15c

STAKES

SECURING 3 - LOG

HURDLE SECTION A - A

SECURING 45cm LOG

HURDLE SECTION B - B

Employ a minimum of three hurdles per siïe.

Figure 4-30 Log hurdles

MIN DEPTH: 4 ROWS

SPACING: IRREGULAR. 1 TO 2m BETWEEN POSTS (AVG 1.6m)

HEIGHT: IRREGULAR 78cm TO 120 cm ABOVE GROUND

AND 160cm BELOWGROUND.

(FRONT) 4 NUMBER OF POSTS-

1.6

DIAMETER OF LOGS. 40 cm

Figure 4—31. Post obstacles.

121

122

v.V

-V

y\

1.5m

1.5m^

Number of posts

WR Long = +1)4

WR Short = “g* + 1

Diagonal - ( —r~ + 1)2 b

Number of Logs

60 Logs = ( ) 2 + 1

Diameter

Number of Logs in wall - (

1 \\ \ \ ^ \INTEKIOR OF

V \ CRIB SHO_ULD RE FIILEO WITH EARTH

Diameter

1.5m

» A LOOS 20cm OIAMElÉV (MIN) 1.5m

L

Figure 4—32 Log cribs.

V.

\ ..v' çrA

i

f?

«m« ENEMY

Figure 4—33. Abatis used as a roadblock

.'. ■ • ■x,‘\ y ■ÿyHh^r 1.5m

l.2m

r 1.5

Figure 4—34. Tetrahedrons

123

CHAPTER 5

MARKING OF BRIDGESAND VEHICLES

Section I. BRIDGES

5-1. MARKING OF BRIDGES

a. Classification. (1) The class number of a bridge represents the safe load—carrying

capacity of a single—lane bridge or a single lane of a multilane bridge under normal crossing conditions. The bridge class number may be a single class number, which will permit either wheeled or tracked vehicles to cross if the vehicle class number is equal to or less than the bridge class number, or it may be a dual class number, which indicates one normal class number for wheeled vehicles and another normal class number for tracked vehicles. Dual classification may be used for bridges with a capacity greater than class 30. For reconnaissance reports and tables, dual class numbers are written with the wheeled class number in parentheses above the tracked vehicle class number.

(2) The normal class number is the largest bridge class number (single or dual) which permits the normal crossing of vehicles whose vehicle class numbers are equal to or less than the bridge class number.

(3) A special class number represents the load—carrying capacity of a bridge under special crossing conditions. These numbers are not posted on standard bridge marking signs, but on supplementary signs.

(4) Width requirements. See table 5—1.

Table 5—1. Bridge Width Requirements — m (ft ).

Bridge class 4-12 13-30 31-60 61-100

One-lane width 2.74 (9)

3.35 (11)

4 03'2")

4.5 04'9")

Two-lane width 5.5 (18)

5.5 (18)

7.32 (24)

8.23 (27)

o. Bridge Signs. (1) For prefabricated bridges and ferries, bridge signs indicate the

class number as given in technical manuals. For bridges fixed in place or for. nonstandard fixed bridges designed in the field, bridge signs shall indicate the class number as determined by methods shown in chapter 7 or TM 5—312.

(2) All single—lane bridge signs are a minimum of 16 inches in diameter. Multilane and dual class bridge signs are at least 20 inches in diameter. Numerals are black on a yellow background with a black border V/z inches wide.

(3) A multi lane bridge has a road way wide enough to carry at least two lanes of traffic simultaneously. If each lane has the same class, the signs are the same as for single-lane bridges. If the lanes are of different classes, each lane has a class sign. Two-lane bridges may carry a combination circular sign (fig. 5-1) which gives the normal two-way classification on the left and the computed one-way classification on the right.

(4) Dual classification is used for bridges with a capacity greater than class 30. Two numbers are then shown on the sign; the upper one for wheeled vehicles, the lower one for tracked vehicles (fig. 5-1). Dual class two-lane bridges may be designated by a composite sign indicating both dual class and combination classes (fig. 5—1 ).

BRIDGES

ONE-WAY TWO-WAY ONE-WAY TWO-WAY

Figure 5—1. Bridge classification signs.

125

126

c. Traffic Control. To expedite passage of vehicles and to prevent damage to the bridge, rigid control of bridge traffic must be maintained. This is done by the following control measures wherever possible.

(1) A traffic park is set up where vehicles can be halted and dispersed in order to avoid congestion, (fig. 5- 2)

FERRY *0 60

CLASS 60 FERRY AHEAD ►

35 ■jr vt TPRROy

■44 ir VWI HIT TELLTALE YOU CANNOT CROSS

6RI06Ë T BWOM NEIÛITT Ltssr

RIDGt •5 KM

TURNOUT A *HEAO ■

LJE M

Figure 5-2. Example of telltale, turnout, and sign arrangement for single-lane bridges.

(2) A turnout area is provided for vehicles to turn off the road and out of the line of traffic. It is meant primarily for vehicles having mechanical troubles, but it can be used as a limited traffic park.

(3) Telltales are provided for bridges having overhead framing, trolley wires, or other features which limit overhead clearance.

(4) A normal crossing is defined as one in which the vehicle class number is equal to or less than the bridge classification number, where vehicles maintain 30.5—meter intervals, and where speed is restricted to 40 kph (25 mph). On floating bridge, sudden stopping or acceleration is forbidden.

(5) Special crossings are authorized by the local tactical commander, under exceptional operating conditions in the field. Special crossings permit a vehicle to cross a bridge (or other crossing means) whose class number is less than that of the vehicle. Special crossings are either caution crossings or risk crossings.

(a) In a caution crossing, vehicles with a classification exceeding the capacity of the bridge by 25 percent are allowed to cross under strict traffic control. Caution crossings require that the vehicle remain on the centerline, maintain a 50—meter distance from other vehicles, not exceed 12 kph (8 mph), not stop, not accelerate, and not shift gears on the bridge.

(b) A risk crossing may be made only on standard prefabricated fixed and floating bridges. Risk crossings are made only in the greatest emergencies. The vehicle moves on the centerline, is the only vehicle on the bridge, does not exceed 5 kph (3 mph), does not stop, does not accelerate, and does not shift gears on the bridge. The vehicle class number must not exceed the published risk class for the type bridge being crossed. After the crossing, and before other traffic is permitted, the engineer officer should reinspect the entire bridge for any damage.

Section II. VEHICLES

5-2. MARKING OF VEHICLES

a. Weight Classification. All vehicles with a gross weight over 3 tons and all trailers with rated payload over 1% tons are assigned classification numbers. These numbers indicate a relationship between the load—carrying capacity of a bridge and the effect produced on it by a vehicle. The effect of the vehicle on the bridge depends upon the gross weight of the vehicle, the weight distribution to the axles, and the speed at which the vehicle crosses the bridge.

127

128

b. Vehicle Signs. (1) Classification Classification numbers assigned to vehicles are

whole numbers ranging from 4 through 150. Front signs on a vehicle are 9 inches in diameter and the side signs are 6 inches in diameter. The signs have black numberals on a yellow background and the numerals are as large as the sign will permit. The fron sign goes above the bumper to the driver's right and below his line of vision, and the side sign on the right side of the vehicle in a place where normal use of the vehicle does not conceal it from view.

(2) Combination Classification With a combination vehicle (two or more single vehicles spaced less than 30.5m apart), the front sign shows the normal vehicle class for the combination with the letter "C" in red above the class number. Each vehicle in the combination carries a side sign which shows its class as a single vehicle. If one vehicle is towing another, they are considered separate, unless they are both on the same span and the distance between them is less than 30.5m. Combination classes are determined as indicated in paragraph 5—3c below.

5-3. EXPEDIENT VEHICLE CLASSIFICATION

In an emergency, temporary vehicle classification can be accomplished by using expedient classification methods. The vehicle should be reclassified by the analytical method as outlined in TM 5—312 or by reference to FM 5—36 as soon as possible to obtain a permanent classification number.

a. Wheeled Vehicles. Expedient classification for wheeled vehicles may be accomplished by the following methods:

(1) Compare the wheel and axle loadings and spacings of the unclassified vehicle with those of a classified vehicle of similar design and then assign a temporary class number.

(2) Assign a temporary class number equal to 85 percent of the gross weight of the vehicle in tons as follows:

TEMPORARY CLASS (wheeled vehicles) = 0.85 \NT

where Wy’= gross weight of vehicle in tons.

The gross weight of the vehicle may be estimated from the tire pressure and tire contact area if no other means are available.

w - A7frN7' 1 2000

where, VJj- = Gross weight of vehicle in tons

Ay = Average tire contact area in square inches (tire in contact with

hard surface) Py = Tire pressure in PSI

Ny = Number of tires

Noie: The tire pressure may be assumed to be 75 psi for 2'/2-ton vehicles or larger if no tire gage is available. For vehicles having unusual load characteristics or odd axle spacings, a more deliberate vehicle classification procedure, as outlined in STANAG 2021, is required.

b. Tracked Vehicles. Expedient classification for tracked vehicles may be accomplished by the following methods:

(1) Compare the ground contact area of the unclassified tracked vehicle with that of a previously classified vehicle to obtain a temporary class number.

(2) Assign a temporary class number equal to the gross weight of the tracked vehicle in tons.

TEMPORARY CLASS (tracked vehicles) = Wy

where, Wy = gross weight in tons

Tracked vehicles can be assumed to be designed for approximately 2,000 pounds (one ton) per square foot of their bearing area (most heavy vehicles are slightly less than this). Thus, the gross weight of the tracked vehicle (Wy) can be estimated by measuring the total ground

contact area of the tracks (square feet) and equating this to the gross weight in tons.

Example: An unclassified tracked vehicle has a ground contact area of 5,500 square inches. Therefore, the area is about 38.2 square feet, and the class of the vehicle is 38.2 or 39, since ground contact area is square feet equals approximate weight of a tracked vehicle in tons, which in turn is approximately equal to class number.

129

130

c. Nonstandard Combinations. The class number of nonstandard combinations of vehicles may be obtained expeditiously as follows:

Combination class = 0.9 (A + B) if A + B 60 Combination class = A + BifA + B 60 A = Class of first vehicle B = Class of second vehicle

d. Adjustment for Other Than Rated Load. An expedient class may.be given to overloaded or underloaded vehicles by adding to or subtracting the difference in loading, in tons, from the normally assigned vehicle class. The expedient classification number is marked with a standard vehicle class sign to indicate temporary classification as shown in figure 5—3.

SINGLE VEHICLE EXPEDIENT CLASS OVERLOAD

8 TON

NORMAL CLASS + OVERLOAD = TEMPORARY CLASS

16 + 3 = 19

Figure 5—3. Expedient class overload.

CHAPTER 6

FLOATING EQUIPMENT

Section I. BRIDGING AND RAFTING EQUIPMENT

6-1. RIVER CROSSING EQUIPMENT

See tables 6— 1 thru 6—11.

6- 2. M4T6 DECK BALK DESIGN

See fig. 6—1 and 6—2.

6-3. OPERATING CHARACTERISTICS OF FLOATING EQUIPMENT

See table 6—12.

6-4. HELICOPTER EMPLOYMENT OF FLOAT MATERIAL

See tables 6—13 and 6—14.

131

132

Table 6-1 River Crossing Equipment

PNEUMATIC ASSAULT

BOAT

TRANS- PORTATION

W/1 2 1/2-TON TRUCK- 20 BOATS w/e MEN- \ BOAT

PROPULSION

11 PADDLES OR 2SHPOBM

TYPE ASSEMBLY

MANUAL, W/

FURNISHED

PUMPS (3)

TYPE CROSSING

PADDLE-ENGR

CREW (3). OBM

ENGR CREW 12)

CAPACITY OR

CLASSIFICATION

ISMEN W/EOUIPMENT

OR 3,375 POUNDS

ASSEMBLY TIME

FULLY LOADED

MAINTAINS

HEADWAY BY

PADDLES IN 5fp* CURRENT;

BY OBM, IN

11 fw CURRENT

ENGINEER

RECON

BOAT

ONE MAN, BY BACKPACK

MANUAL, W/

FURNISHED

PUMPS (3)

PADDLE-ENGR

CREW (3)

3 MEN W/EQUIPMENT

OR 600 POUNDS

FULLY LOADED

MAINTAINS HEADWAY IN

4 fm CURRENT

ARMORED

PERSONNEL

CARRIER

SELF

PROPELLED

SELF-

PROPELLED

12 MEN W/EQUIPMENT ORGANIC ARMORED

ANDMECH INF

UNITS

BRIDGE

ERECTION

BOAT

ONE 2 1/2-TON

W/ POLE TRAILER/BOAT

SELF

PROPELLED (TWO 90 HP

MARINE DRIVE ENGINES)

9 MEN W/EQUIPMENT

OR 3.000 POUNDS

20 MIN (TRANS-

PORTED

IN TWO SECTiONS)

PRIMARY USE IS

HEAVY FLOATING

BRIDGE ASSEMBLE

AND RAFT

PROPULSION

ALUMINUM

FOOTBRIDGE TWO 2 Î/2-TON

TRUCKS W/TWQ POLE TRAIL- ERS/SET

STEAM VELOCITY

Ip»

75 MEN/

MIN

40 MEN/

MIN

25 MEN/ MIN

60 MEN/

MIN

15 MIN SITE

PREPARA-

TION

t 1 MIN FOR EACH 15 FT

OF BRIDGE

32 MEN/

MIN

20 MEN/ MIN

PADDLED

OR OBM

1/4 TON tTRAILER 6fpt 10 MIN

ANCHORED BY

EXPEDIENT

OVERHEAD

CABLE-BRIDLE

LINE SYSTEM

CONSIDERED

EXPEDIENT

RAFT

Table 6-1. River Crossing Equipment (com)

EQUIPMENT TRANSPORTATION PROPULSION

LIGHT TACTICAL RAFT/BRI DGE

TWO 2 l/J.TON TRUCKS AND ONE POLE

MINIMUM OF

TWO 25-HP OBM

ONE OUT- BOARD MOTOR PER PONTON IS RECOM-

MENDED

CAPACITY OR

CLASSIFICATION

TYPE ASSEMBLY

TYPE :ROSSINC

ASSEMBLY TIME

4 PONTON/1 BAY W/O ARTICU- LATORS

4 PONTON y3 BAY W/O ARTICU- LATORS

4 PONTON/4 BAY W/ ARTIC- ULATORS



6 PONTON/4 BAY W/ ARTIC— ULATORS

6 PONTON/4 BAY W/O ARTIC- ULATORS

0 PONTON/5 BAY W/O ARTIC- ULATORS

BRIDGE

33’ LOADING SPACE*

33* LOADING SPACE

44' LOADING SPACE

55' LOADING SPACE

55' LOADING SPACE

44' LOADING SPACE

44’ LOADING SPACE

65' LOADING SPACE

150 FT

PER HR.

133

134

Table 6—¡ River Crossing Equipment (cont)

EQUIP- MENT

TRANS- PORTATION

TYPE ASSEMBLY

TYPE CROSSING

CAPACITY OR

CLASSIFICATION

ASSEMBLY TIME

M4Ti FLOATING BRIDGE RAFT

ONE BRIDGE TRUCK/ IS' OF BRIDGE

II BRIDGE TRUCKS/SET WITH ACCESSORIES

NORMAL BRIDGE

STREAM VELOCITY FPS

REIN- FORCED BRIDGE

ONE BRIDGE TRUCK/ FLOAT + ONE TRUCK WITH ACCESSORIES

TWO BRIDGE ERECTION BOATS/RAFT

«•FLOAT NORMAL RAFT

«■FLOAT REIN FORCED RAFT

SEE TABLE I

KEDGE ANCHORS, SHOREGUYS/OR COMBINATION OVERHEAD CABLE BRIDLELINE MAY BE USED FOR ANCHORAGE

BTB" LOADING

SPACE5

SB'A" LOADING SPACE

Table 6—1 River Crossing Equipment (coni)

EQUIP- MENT

TYPE ASSEMBLY

{•FLOAT

NORMAL RAFT

S FLOAT REIN- FORCED RAFT

4 FLOAT REIN- FORCED RAFT

TYPE CROSSING

CLASSIFICATION

STREAM VELOCITY F~

ASSEMBLY TIME

ss ♦0

70

75 65 70 75 BO

50 55

60

65 70 75 65 70

U

40 45 SO 45 50

55 60 45 50

ASSEMBLY TIME BASED ON > Nee'S A 30 EM

SO' LOADING SPACE

SJ'4" LOADING SPACE

MOBILE ASSAULT BRIDGE T

FERRY

SELF- PROPELLED

SELF-

PROPELLED FERRY 2 END UNITS

62

60

60 62

IT 62

60 62

Soo FT/HR

6 MIN

S MIN

10 MIN

NEED ONLYMAB CREW FOR ASSEMBLY

* DISTRIBUTED LOADCAP U SHORT TONS U SHORT TONS

72 SHORT TONS

00 SHORT TONS

100 SHORT TONS

NOTE. MAB CLASS SHOULD BE REDUCED BY M% IN CURRENT ABOVE H F PS.

135

136

REMARKS EQUIP MENT

TRANS- PROPUL- PORTATION SION

RIBBON BRIDGE/ RAFT

1 EA M812 TRANS- PORTER WILL ACCOM- MODATE EITHER 1 EA. INTERIOR BAY, 1 EA. RAMP BAY. OR 1 EA. 27' BRIDGE ERECTION BOAT

TYPE ASSEMBLY

TYPE CROSSING

CAPACITY OR

CLASSIFICATION STREAM VELOCITY FPS

ASSEMBLY TIME

3 6 7 IV

NORMAL BRIDGE

_N_

C

66 66

70 70

60

66

60

65

46

50 -

6 MIN/BAY ANCHORAGE MAY BE BY TRANSPORTER OR EREC- TION BOATS (TEMPORARY SEE TABLE 6-10) OR BY METHODS DESCRIBED FOR CLASS 60 OR M4T6 AS OUTLINED IN CHAPTER 13. TM 6-210 CLASSES GIVEN ARE FOR TRACKED VEHICLES.

2 BRIDGE ERECTION BOATS

3-BAY LONGITU- DINAL

4-BAY

N 26 6 MIN/BAY 44' LOAD SPACE

LONGITU- DINAL 6-BAY LONGITU- DINAL

[*)3 BRIDGE ERECTION BOATS

3- BAY CONVEN- TIONAL

4- BAY CONVEN- TIONAL

5-BAY CONVEN- TIONAL

66' LOAD SPACE

68' LOAD SPACE

22' LOAD SPACE

44' LOAD SPACE

66' LOAD SPACE

Table 6-1. River Crossing Equipment (coni)

’ALL ASSEMBLY TIMES ARE ESTIMATED USING TRAINED TROOPS, IN GOOD WEATHER,

IN DAYLIGHT. FOR UNTRAINED TROOPS ADD 30%; FOR INCLEMENT WEATHER (40°, 80°, RAIN OR SNOW) ADD 30%; FOR BLACKOUT CONDITIONS ADD 50%. ALL PERCENT- AGES CALCULATED FROM ORIGINAL TIME. EX. AT NIGHT WITH UNTRAINED TROOPS = 180% OF GIVEN TIME.

2ALL ASSEMBLY TIMES EXCLUDE SITE PREPARATION.

CLASSIFICATION WHEELED VEHICLE/TRACKED VEHICLE. r**. CO

4LTR LOADING SPACE MEASURED FROM END OF NEAR SHORE BAY TO END OF FAR

SHORE BAY (EXCLUDES RAMP SECTIONS).

5M4T6 LOADING SPACE MEASURED FROM NEAR SHORE END STIFFENER TO FAR SHORE END STIFFENER (EXCLUDES END RAMPS).

DISTRIBUTED LOAD CAPACITY IS THE WEIGHT IN SHORT TONS THAT CAN BE

CARRIED BY THE RAFT.

CLASSIFICATION OF MAB REFERS TO HEAVIEST VEHICLE WHICH CAN BE LOADED

RESTRICTED BY END RAMP CLASSIFICATION.

138

Table 6-2 Aluminum Footbridge Data

BRIDGE SET BASIS OF ISSUE SUGGESTED WORKING PARTY

DETAIL

NORMAL ASSEMBLY 472 FT 6 IN

LIGHT VEHICLE BRIDGE: 100 FT

EXPEDIENT RAFTS: 3

MAJOR ITEMS:

PONTONS. 42 TREADWAYS: 42

ONE SET TO EACH ENGINEER FLOAT

BRIDGE COMPANY (CORPS)

NEAR-SHORE ANCHOR CABLE FAR-SHORE ANCHOR CABLE

BRIDLE LINE GUY LINE SHORE ASSEMBLY ASSEMBLY CARRYING

RIVER ASSEMBLY

HANDRAIL

PLUS 2 EM PER 100 FT OF BRIDGE

Table 6—3 Light Tactical Raft Data

BRIDGE SET BASIS OF ISSUE SUGGESTED WORKING PARTY

DETAIL

ASSEMBLY AS

BRIDGE:

44 FT OF LIGHT

VEHICULAR BRIDGE

ASSEMBLY AS RAFT: ONE 4-PONTON

4-BAY OR ONE

4-PONTON 3- BAY RAFT

TWO SETS TO EACH

DIV ENGR BN.

SIX SETS TO CORPS

FLOAT BRIDGE COMPANIES.

RAFT OR BRIDGE PONTON CARRYING DECK PANEL CARRYING PONTON CONNECTING PONTON DELIVERY DECK PANEL UNLOADING

BRIDGE ONLY BRIDGE CONNECTING NEAR SHORE ABUTMENT FAR SHORE ABUTMENT ANCHORAGE SYSTEM

10 10*

6

2 5

‘SAME PERSONNEL AND DECK PANEL

CAN BE USED FOR PONTON CARRYING CREWS.

Table 6-4. M4T6 Raft/Bridge Data

BASIS OF ISSUE SUGGESTED WORKING PARTY

DETAIL

ONE NORMAL FLOAT- ING BRIDGE. 141 «1 BIN. OR ONE 4-FLOAT AND 1 6-FLOAT REIN- FORCED RAFT. OR TWO FLOATING BRIDGES. 76 FT. ONE WITHOUT REINFORC- ING BALK ON END FLOAT. OR THREE 38-FT 4-IN FIXED SPANS.

DIVISIONAL ENGINEER BN FLOAT BRIDGE CO. 4 SETS. CORPS ENGINEER FLOAT BRIDGE CO.

6 SETS

FLOAT INFLATION SADDLE ASSEMBLY |W/CRANE) SADDLE ASSEMBLY W/O CRANE) ASSEMBLED FLOAT DELIVERY BALK CARRYING BALK PLACING ANCHORAGE * NEAR SHORE ABUTMENT* FAR SHORE ABUTMENT*

•NEEDED FOR BRIDGE ONLY

8 20

4 40 12 12 8 8

Table 6-5. M4T6 Bridge Assembly Time

Langth (Feet) (Normal AsaamUy)

150

200

250

300

350

400

500

600

700

800

1000

1200

Unit Sira

1 Company

2 Com pan in

3 Compañía

Number of Assembty Sita

2

2

2

3

3

4

5

6

6

6

8

6

Time (Hours)

4

5

6

4

5

6K

8

4

5- 7

6- 8

7- 10

8- 12

NOTE: Sea figure 6-1 for deck balk layout pattern.

139

140

Table 6-6 Deck Balk Fixed Span Data

CapKity For Specified Span Length (Ft) And Dedc/Roadway Ratio

Type Crossing

Normal

23'4"

22

18

125

100

22

18

85

65

wo"

22

16

90

70

24

18

90

70

38’4"

22

J!

45

35

22

Jj6

50

40

26

18

55

50

20

16

24

25

22

18

24

25

22

16

30

30

45-0"

24

J£

30

30

40 40

35 35

26

J6

45

40

Caution

120

100

100

80

100

80

105

85

82

50

40

35

46

40

48

40

51

43

51

43

56

46

Risk

120

100

110

80

110

90

115

95

90

67

47

40

54

45

54

46

60

49

60

49

66

53

66

53

Component

Pans2 Number Of Parti Needed Fot Assembly

Normal Balk 22 33 33 36 44 44 48 62 50 56 55 60 60 66 65

Short Balk 22 12 22 22 24 26 10 11 11 12 12 13 13

-lanercd Balls. _aa_ -4Z_ ji- ja. 3i 32. 31 21 J2_ 47 43 4fi_ .41. J1

Balk Connecting Stiffener

1F igure includes two complete ramps

2All completa spans also require 4 bearing plates, 4 long coyer platea, and 4 dtort cover plates

3see figure 6-2 for deck balk layout pattern

OVERALL LENGTH* 42'3-

OVERALL WIDTH*

HEIGHT* 12'

WEIGHT (TONS) - INTERIOR BAY 23.25

WEIGHT (TONS) - END BAY 25.80

TURNING RADIUS* 40'

SPEED - LAND TRAVEL 42 MPH

LENGTH - INTERIOR BAY 26'

LENGTH - END BAY 36'

RAMP ARTICULATION

ABOVE HORIZONTAL

BELOW HORIZONTAL

ANY

6'3"

•REFERS TO BRIDGE TRANSPORTER

COMPONENTS 215 M (700 ) OF CLASS 60 BRIDGE OR 6 EA. 7-BAY RAFTS. OR ANY COMBINATION OF 30 INTERIOR BAYS AND 12-RAMP BAYS.

BASIS OF ISSUE ONE SET TO EACH RIBBON BR CO

ROADWAY WIDTH 4.1 M (13'6") PLUS2 EA. 1.2 M (4’) WALKWAYS

INTERIOR BAY - LENGTH WIDTH WEIGHT

6.7 M (22’) 8.1 M (26'6") 4.631 KG (10.210 LBS)

RAMP BAY - LENGTH WIDTH WEIGHT

5.6 M (18'4") 8.1 M <26'6")

4.445 KG (9,800 LBS)

SITE CONSIDERATIONS WATER DEPTH BANK HEIGHT SHORE SLOPE

— 112 CM (44") — 1.5 M (5') — 20%

141

142

Table 6—9 Ribbon Bridge Assembly Dala

BRIDGE LENGTH

(APPROX) METERS FEET

18

24

31

38

45

51 58

65

71

78

58

80

102

124

146

168 190

212

234

256

BRIDGE BAYS RAMP INTERIOR

1

2

3

4

5

6 7

8

9

10

LAUNCHING SITES

DESIRED

2

2

2 2

2

3 3

3

3

3

BRIDGE ERECTION BOATS

SOTES 1. The number of boats shown in "Needed" column is based on an average stream velocity of about 0.91 to 1 5 meters (3 to 5 feet) per second.

2. Stream velocities determine the number of bridge erection boats to be added for a given increase in bridge length (number of interior bays added)

VELOCITY MPS EPS

INTERIOR BAYS ADDED BOATS NEEDED

0 to 0.9 0 to 3 Up to 6

0.9 to 1.8 3 to 6 Up to 3

1.8 to 2.4 6 to 8 Up to 3

3. Safety boats are included; backup boats are not included.

1

1

1

Table 6—10 Ribbon Bridge—Bridge Erection Boats Used

for Short-Term Anchorage

STREAM VELOCITY

MPS

RATIO OF ERECTION BOATS

TO INTERIOR BAYS

SPACING BETWEEN BOATS

METERS

0- .91

.91- 1 8

18-24

Over 2.4

0-3

3-6

1 6

1 4

1.3

As required

40

27

20

As required

66

As required

\OTtS 1 Safety and backup boats are not included

2 Add at least two backup boats and one safety boat for each short-term anchorage

Table 6-//. Ribbon Bridge - Typical Crew Duties and Organization

BRIDGE ON RAFT LENGTH

(Number of Bars)

12 15 SUPERVISES ENTIRE

OPERATION NCOIC

CREW

MOTOR PARK

PREPARES TRANSPORTERS/ BAYS/BOATS FOR LAUNCH- ING, PARKS TRANSPORTERS AFTER LAUNCH; CONTROLS TRAFFIC IN PARK.

DRIVES TRANSPORTERS TO LAUNCHING SITES AND LAUNCHES BAYS/BOATS. (SEE NOTE 1.)

î: ASSISTS IN BAY/BOAT LAUNCHING.

BRIDGE

BOAT

OPERATES BRIDGE EREC- TION BOATS WITH THREE MEN ASSIGNED TO EACH BOAT TO SECURE BAYS AND ASSISTS IN THE ASSEMBLY AND DISASSEMBLY OF BRIDGE OR RAFT. (SEE NOTE 2.)

ANCHORAGE INSTALLS ANCHOR CABLES. BRIDLE LINES, ANCHOR TOWERS, DEADMEN, AND SHORE GUYS.

BRIDGE CENTER

LINE/RAFT ASSY SITE

D2DSfljS0EgSB5B3lE5

CONNECTS BAYS. PREPARES BRIDGE FOR TRAFFIC. DIRECTS USE OF TRANS- PORTERS WHEN USED FOR BRIDGE CLOSURE OR ANCHORAGE (SEE NOTE 3.)

NOTES: 1. DURING LAUNCHING AND RETRIEVING OPERATIONS, AN ASSISTANT OPERATOR

IS ASSIGNED TO EACH TRANSPORTER. 2. DOES NOT INCLUDE PERSONNEL FOR SAFETY BOATS OR BACKUP BOATS. 3. EM MAY BE INCREASED TO SIX, DEPENDING ON LENGTH OF BRIDGE AND

VELOCITY OF STREAM. * TWO LAUNCHING SITES. : THREE LAUNCHING SITES

143

144

NEAR SHORE

6'—8'

AIK CONNECTING STIFFENER

r

NORMAL RAT PATTERN

OFFSET SADDLE ADAPTER 8—4

= = ^ 6—8

IOT® © 11 13

r 6—8

I END SE< SECTION 'NORMAL

SADDLE ADAPTER PATTERN 8—8

t RALK CONNECTING STIFFENER

4» OVERHANG-^, i PATTERN

®/ _®

B —8

Figure 6-1. Balk pattern, M4T6 floating bridge.

TIMBER SILL

I*- 8 4'1 -4-ió-0,,*|'*'8-4-,-4-6,-8,,--ê,-4"—

J. A U U iL u Li

KEY BALK ' _I PATTERN

m

f m T TAPERED / CURB

BALK SHORT BALK CURB STIFFENER \ TAPERED BALK

NORMAL BALK

(T) LAYOUT

STIFFENER (B)

STIFFENER |4)

STIFFENER (3)

STIFFENER |2)

STIFFENER (I)

C

J—r 0-4*

6-0‘

0‘-4'

4 6'-0'‘

STIFFENER |A)

@ H - FRAME FOR BALK FIXED SPAN

Figure 6—2 Layout of deck balk jixed bridges

145

146

Table 6-12. Round-Trip Travel Times

Equipment

Time in Min Per Round Trip

Stream Width in Feet 260 600 1000

Pneumatic assault Boat - Paddled

Pneumatic assault Boat - Outboard Motors

Ribbon Bridge/Raft

•M4T6/LTR

‘Mobile assault bridge

10 10

10

10

16

15

15

‘No. of rafts that can be used efficiently at one time ” 250' — 1, 500' - 2. 1000' - 3.

Table 6—13. Helicopter Capabilities

Helicopter Capability

Type Helicopter Operational Load^ Maximum Load*

UH-1

CH-47

CH-54

3,116

10,144

15,400

4,000

16,000

20,760

Ôperational load is the amount that can be carried with a full fuel load on a standard day at saa level.

Maximum load is the amount that can be lifted without structurally damaging the helicopter.

Table 6—14. Typical Loads and Helicopter Requirements

Item of Equipment Weight (lbs) Recommended Carrier

M4T6 FIXED SPANS

23'4‘* H-Frjmo 30' H-F rame 38'4" H Frame 45' H-Frame 23'4" Fixed Span Complete^ 30’ Fixed Span Complete)(Load

No. 48)2 38'4" Fixed Span Complete1 (Load

No. 49)2 45' Fixed Span Complete1

Single Trestle w/Bracing 15'Trestle Arrangement

w/22 Normal Balk (Load No. 57) ^ w/11 Normal Balk

8'4'' Trestle Arrangement w/22 Short Balk w/11 Short Balk

HEAVY FLOATING BRIDGE EQUIPMENT

27' Bridges Erection Boat (Load No. 61) 2

Bow Section Stern Section w/Fuel ■* Water w/o Fuel + Water

Aluminum Balk Light Bundle (35 Normal Balk) (Load No. 51) 2

Heavy Bundle (63 Normal Balk) (Load No. 52) 2

Normal Balk (ea) Short Balk (ea) Tapered Balk (ea)

2.800 3,700 4.500 5.100

12.900 15,600

18,800

20.900 3,400

11,800 8.100

9.500 8,000

6,800

1,150

5,650 4.900

7.900

14,200

225 122 100

UH-1 CH-47 CH-47 CH-47 CH-54 CH-54

CH-54

CH-54 UH-1

CH-54 CH-47

CH-47 CH-47

CH-47

CH-47 CH-47

CH-47

CH-54

14/

148 Table 6—14. Typical Loads and Helicopter Requirements (cont)

Item of Equipment Weight (lbs) Recommended Carrier

M4T6 Float w/Saddle Assembly and Stiffeners (Load No. 53) 2

M4T6 Float w/Saddle Assembly, Stiffeners and 22 Normal Balk (Load No. 53) 2

Two NI4T6 Floats w/Saddle Assemblies, Stiffeners, and 10 Normal Balk (Load Nos. 55. 56) 2

LIGHT FLOATING BRIDGE EQUIPMENT

Light Tactical Raft Ponton Load (8 Half Pontons w/Cradle) (Load No. 58)2

Deck Load (4 Bays Complete w/Articulators (Load No. 60) 2

Aluminum Footbridge One Set (472'6") Crated One Set (472'6") Uncrated

Pneumatic Assault Boat

RIBBON BRIDGE/RAFT

Interior Bay Ramp Bay

6,700

11,700

16,900

6,000

10,500

11,000 9,100

250

10,210 9,800

CH-47

CH-54

CH-54

CH-47

CH-47

CH-54 CH-47

CH-47 CH-47

Information refers to 22/18 fixed span including 36 tapered balk for ramps and 4 bearing plates

Load No. refers to loads described in TM 55—450—11 "Helicopter External Loads"

Section II. ANCHORAGE SYSTEMS

6-5. BASIC CONSIDERATIONS

Anchorage must be provided on float bridges to secure the bridges and keep them alined. The selection of an anchorage system is influenced by the width of the river, its current, stage variation, debris flow, the river bed, embankments, and resources available. The anchorage system is designed to withstand the worst conditions anticipated. The basic anchorage systems used are shore guys, kedge anchors, a combination of both, and overhead cable—bridle line systems. The strongest standard method of anchoring a floating bridge is the overhead cable-bridle system supplemented by shore guys. When combinations of anchorage systems are used, the load cannot be divided between systems — one must supplement the other.

6-6. TYPES OF ANCHORAGE SYSTEMS

See fig. 6—3 thru 6—7 and table 6--15.

6-7. OVERHEAD CABLE-BRIDLE LINE SYSTEM DESIGN

a Anchor Cable Layout (fig. 6—8).

149

150

CURRENT 0-3 FPS

J UPSTREAM KEDGE ANCHORS EVERY FLOATING SUPPORT

ñññññftnhhhnhnhnhhhhhhñ gu'uuu'uu'uJ

APPROACH GUYS

DOWNSTREAM KEDGE ANCHORS EVERY 3RD FLOATING SUPPORT.

EVERY FLOATING SUPPORT WITH REVERSAL CURRENT FROM 0 TO 3FPS

Figure 6-3 Location of hedge anchors

DEADMEN LOCATED ABOVE HIGH WATER LEVEL TO PREVENT WASHOUT

43°

.m n n

CURRENT 0-3FPS

l

jouruuuuu / nnnn

UPSTREAM SHORE GUYS (EVERY 6TH FLOATING

SUPPORT)

rrr rrrr T T T T ^'ü^'ü1 JÜTO'Ü

SHORE GUYS CONSTRUCTED FROM NOT LESS THAN 'h INCH IPS WIRE ROPE

DOWNSTREAM SHORE GUYS EVERY 10TH FLOATING SUPPORT; (EVERY 6TH FLOATING SUPPORT IF REVERSAL CURRENT EXCEEDS 3FPS)

APPROACH ^ GUYS

h'lKurc ft-4 Loca I ion of slmn- nuv.\.

152

CURRENT

O - 5 FPS

DEADMEN LOCATED ABOVE

HIGH WATER LEVEL TO

PREVENT WASHOUT

UPSTREAM SHORE GUYS

(EVERY 6 FLOATING SUPPORTS)

KEDGE ANCHORS EVERY ' FLOATING SUPPORT \

norw nn nan f I l I I 1 I T TTTTJ I T I 1.1 uUUUU uuuuuu uuuuuu

APPROACH

v GUYS

DOWNSTREAM SHORE GUYS EVERY 10TH FLOATING SUPPORT

AND KEDGE ANCHORS EVERY 3RD FLOATING SUPPORT

NOTE: REVERSAL CURRENTS FROM 3 TO 5 FPS REQUIRE SHORE/ relive CWCD CTU PI OATIMfí SUPPORT AND KEDGE ANCHORS ON I GUYS EVER 6TH FLOATING SUPPORT AND KEDGE ANCHORS ON

EVERY FLOATING SUPPORT BOTH UPSTREAM AND DOWN.

Figure 6—5 Employment of combination system.

CURRENT 0-11 FPS

DEADMAN ANCHOR TOWER

BRIDLE LINES ANCHOR

CABLE

uuuuuuu ÜUÜ uuuuu

NOTE: EITHER SHORE GUYS (EVERY lOth SUPPORT) OR KEDOf ANCHORS (EVERY 3rd SUPPORT ) MUST BE USED DOWNSTREAM.

NOTE: REVERSAL CURRENT MAY REQUIRE FULL ANCHORAGE DOWNSTREAM. SHORE GUYS, KEDGE ANCHORS, COMBINATION, OR SECOND CABLE BRIDIE LINE SYSTEM MAY BE USED. DEPENDING ON STRENGTH OF REVERSAL CURRENT.

Figure f>-6. Single upstream overhead cable—bridle line system.

153

154

CURRENT

ANCHOR TOWERS

DEADMEN

ANCHOR CARLES

11 1

SHORE GUYS SUPPLEMENT OVERHEAD ANCHORAGE x

WHERE SEVERE CURRENT CONDITIONS EXIST

NOT I MUlTIfLI C A til S CAN ALSO tl PLACID ON SINOLI III Of TOWKftt.

USE OF MORI THAN ONE OVERHEAD CABLE (TABLE A-lé) A DOWNSTREAM

ANCHOR CABLE MAY BE NEEDED IF A TIDAL ACTION EXISTS IN A RIVER

THE CALCULATIONS FOR A DOUBLE OR TRIPLE OVERHEAD CABLE SYSTEM

ARE THE SAME AS FOR A SINGLE CABLE SYSTEM

Figure 6—7. Floating bridge with multiple overhead cable system and downstream overhead cable anchorage

Table 6—15. Anchorage Systems/Characteristics

Type Capacity Remarks

Kedge 0—3 fps Anchor line must be a minimum of 10 times the

Anchors depth of the water; 20 times depth is desirable. River bed must permit anchor flukes to dig in. See figure 6-3.

Shore 0—3 fps Guys attached at 45° angle. Shore anchorage Guys point needed for guy lines (soil must hold dead-

man). See figure 6—4.

Combina- tion Kedge & Shore Guys

0-5 fps See remarks for separate systems. See figure 6—5.

Over- head Cable- Bridle Line

0—11 fps See para 6—7 for design. 1200 ft maximum unsup- ported cable length. See figure 6-6.

NOTE All anchorage systems require approach guys to the floating supports nearest the shores.

155

156

i

(1) ANCHOR CABLE-ELEVATION LAYOUT

KEY TO SYMBOLS

B = MEAN BANK HEIGHT C = DISTANCE TOWER TO DEADMAN ON CENTERLINE D = DEPTH OF DEADMAN G = LENGTH OF BRIDGE H = ANCHOR TOWER HEIGTH L = DISTANCE BETWEEN TOWER ANCHOR

O' = OFFSET BRIDGE CENTERLINE TO ANCHOR TOWER CENTERLINE O3 ^ OFFSET ANCHOR TOWER CENTERLINE TO DEADMAN

S = UNSTRESSED SAG IN ANCHOR CABLE R = GROUNDBEARING STRENGTH IN POUNDS PER SQUARE FOOT T = CABLE TENSION IN POUNDS

<2> ANCHOR CABLE-BRIDLE LINE LAYOUT PLAN

BRIOOE CENTER LINE

DIAOMAN

CENTERLINE

I UUU U U UUU j]

Figure 6—8. Overhead cable-bridle line anchorage system.

b. Anchor Cable Design. (1) Determine the size and number of anchorage cables that are

required (tables 6—16 thru 6—18). Round up to the next higher value for bridge span (G) shown in table 6—16. Using known current or next higher stream velocity, select the cable size for the minimum number of cables.

(2) Determine the distance between towers (L). Place the towers the same distance from each bank.

Rule of Thumb (R of T); L = (1.1 x gap) + 100' (3) Determine cable sag In feet (S) (fig. 6—8 and 6—9).

(4) Determine required height of tower (H), when sag (S) and bank height (B) are known.

R of T: H = 3' + S — B (Minimum allowable H)

Mole: Actual height of tower (H) will Be the next higher size shown in table 6—19.

(5) Determine the distance from the bridge centerline to the anchor tower centerline (0y ).

R of T; S = 0.02 L

NOTE: VERTICAL DISTANCES EXAGGERATED

Figure 6—9. Cable sag.

R of T (a) If bank height (B) is less than 15'; 0y = H + 50'

(b) If (B) is greater than 15'; 0y = H + B + 35'

157

158

Table fi- I fi Anchor Cable Requirements ¡or Overhead Cable-Bridle Line Svstein - M4Tfi Bridge

Bridge Spsn (G)

(ft)

Typ« Bridg»

Aoembly* Singla S tin

Sita (IN.) and Numbar of Cablat for Soacified Stream Velocitws*

Tripla Singla

7 foi Dual Triple Singla

9 foi Triple Single

-ILifil- Duel Triple

Mormal 1 / 2

Reinforced 3 / 4

1

8

400 3 / 4

1

4

Reinforced 3 / 4

1 K 4

1

600 Normal 3 / 4

5 / 8

1

4

1

2

1

4

7 / 8

Reinforced 3 / 4

1 V 8

1

2

1 1

2

\

8

800 1

1/ 8

3

8

1 1/

1 K 2

1 K 8

Reinforced

1

'B

Table 6-16. Anchor Cable Requirements for Overhead Cable-Bridle Line System — M4T6 Bridge (cont)

BRIDGE

SPAN (G)

(ft)

SIZE (IN.) AND NU38ER OF CABLES FOR SPECIFIED STREAM VELOCITIES*

BRIDGE

ASSEMBLY SINGLE QDUAL I TRIPLE ¡SINGLE1

7/0 D 3/4 Q 1 1/4 H 1

REINFORCED 1 1/4

7 FPS I

DUAL|TRIPLE|SÎ ISINGLEQDUAL

7/8 ¡11/2

3/4 D 1 1/2 1 1/4 fl 1

1 3/B

TRIPLE Í SINGLE

REINFORCED 1 3/B

7/8 I 3/4

1 1/8 7/8

13/8 11/8

»Q i i

• 1 3/8 1 1/4

NOTE 4 BASED UPON IMPROVED PLOW STEEL CABLE AND 2 PERCENT INITIAL CABLE SAG.

** UNSAFE. BASED ON CABLE SPAN EQUAL TO 1.1 TIMES WET GAP PLUS 100 FEET. "** CLASS 60 ANCHORAGE REQUIREMENTS ARE THE SAME AS M4T6. ROUND UP TO

NEXT HIGHER BRIDGE SPAN.

160

Table 6-1 7. Anchor Cable Requirements — Light Tactical Bridge

Span in feet (Wet gap)

200

300

400

500

600

Maximum stream velocity (fps)

3

8

3

8

1

2

1

2

5

8

3

8

1

2

1

2

5

8

5

8

1

2

5

8

5

8

5

8

3

4

11

1

2

3

4

3

4

3

4

7

8

Table 6—IB. Anchor Cable Requirements — Aluminum Footbridge

CURRENT VELOCITY TYPE ANCHORAGE WHERE ATTACHED TO BRIDGE

STILL WATER MIDDLE OF TREADWAY STRINGER OF EVERY 3d BAY ON BOTH SIDES OF BRIDGE

STILL WATER ANCHOR CABLE W/BRIDLE LINES

THROUGH THE BOW OF THE PONTON TO THE TREADWAY STRINGER OF EVERY 3d BAY ON BOTH SIDES OF THE BRIDGE

3 fps OR LESS

ANCHOR CABLE W/BRIDLE LINES

THROUGH THE BOW OF THE PONTON TO THE TREADWAY STRINGER OF EVERY 2d BAY ON UPSTREAM SIDE.

4 THROUGH 11 fps

ANCHOR CABLE W/BRIDLE LINES

THROUGH THE BOW OF THE PONTON TO THE TREADWAY STRINGER OF EVERY BAY ON THE UPSTREAM SIDE

Table 6—19. Possible Anchor Tower Heights

Number of Tower Sectioni Height of Tower

Cap, base, and pivot unit 3 ft avi in

14 ft 6K in 25 ft 4% in 36 ft 2V. in 47 ft 'A in 57 ft 10% in 68 ft S'A in

More Minimum of 3 ft 8% in cán be used as tower height. c. Deadman

(1) Depth ol cleailinati (D). The deadman should be buried as deep as necessary for good bearing surface against undisturbed soil. R of T; D = 7' or 1' less than the depth of the water table - whichever is less. Minimum (D) = 3'. (D) is measured from the ground level to the mean depth of timber. See figures 6- 10 and 6—11. (Always maintain at least 1 foot of undisturbed soil between the bottom of the deadman and the ground water level.)

(2) Tower to deadman distance Determine tower to deadman distance (C) and deadman offset (02)- See figure 6—8.

(a) Select the approximate position for the deadman based upon site conditions.

(b) c = (H + D)_ . Minimum permissible value for C is H + D (slope Slope Ratio

ratio of 1/1 ). Try to let C = IH + D ) 1/4

(c) Read required value of 0 from table 6—20 (O2/) for C used. The

actual value of O2 (07^) for a calculated value of C can be computed using

the following formula:

0-,A =— x 07/(07/read from table 6—20). ¿A 100

161

162

Table 6—20. Values of O2 Per Hundred Feet of C

Current velocities

Normnl assembly

Reinforced assembly

Offset upstream (Os/) in feet

per hundred feet of C

3 fps 5 fps

7 fps

9 fps

11 fps

3 fps

5 fps

7 fps 9 fps

11 fps

9 11

14

17

19 23

\<)TI\ Use current velocity known or next higher current to determine O2

(3) Determine deadman size. Determine lumber available and check length (L), thickness (t), and face height (f) or (d) of available timber. Use the largest dimension of the deadman timber for bearing and refer to it as the face height (f). The face height for a log deadman is its diameter (d) (fig. 6-10 thru 6-12).

(a) Enter nomograph "A" (fig. 6—13) at Column A with D and slope ratio (1/4).

(b) Locate cable diameter and type on Column B. Connect the points from Column A to Column B and extend the line to Column C.

(c) Extend the line horizontally to the face height curve and read the deadman length and thickness from the top and/or bottom of the graph.

(4) Bearing plate design. (ai Flat bearing plate. Enter nomograph "B" (fig. 6-14) with size

and cable type. From the deadman face height curve, determine the bearing plate height, thickness, and length.

(b) Formed bearing plate. Enter nomograph "C" (fig. 6—15) with size and cable type. From the deadman face height curve determine the bearing plate thickness and length.

3 O0.

c%

o' GROUND WAHR LEVEL C^V

Figure 6—10 Timber deadman.

FACI OF LOO W<

Figure 6-II. Log deadman.

163

164

H+D

O I

SLOPE OF CABLE = iíi£

KEY: D = MEAN DEPTH OF DEADMAN L = LENGTH OF DEADMAN ( = FACE HEIGHT OF (TIMBER) d = DIAMETER FACE HEIGHT OF LOG DEADMAN t = THICKNESS OF DEADMAN i = WIDTH OF CABLE SLOT (NORMALLY V - O’)

C = DISTANCE OF DEADMAN BEHIND TOWER H = ACTUAL TOWER HEIGHT

Figure 6—12. Dead man dimensions.

•'O" U/H)

7-U/4)_

7' (1/3)

DIAM OF CABLE IN INCHES

ALLOWABLE WORKING STRESS OF CABLE IN

1,000 LBS /IN. S. F • 5 0

— 6'(1/4)

6' (1/3)

EXAMPLE PROBLE

&'t1/4>—( ^

8'(1/3) —

.4* (1/4)

4'(1/3)

IPS PS MPS

1 1/2 1 1/2 p"

LENGTH OF TIMBER OEADMAN IN FEET (L)

76 9 10 11 12 13 14 15 16 17

r (1/4)—

1' (1/3)“

’a--

z

/A 7/

m u

LENGTH OF TIMBER OEADMAN

i/B 7 8 9 10 11 12 13

FEET

, , |l 11111 M 1111111 M M IMU i 5 6 7 8 9 101112 13 141516 17 1819202122 23

TIMBER (MIN. THICKNESS) IN INCHES (T)

NOTE CARE MUST BE TAKEN NOT TO SELECT A LOG DEADMAN IN THE DARKENED AREA BECAUSE IN THIS AREA THE LOG WILL FAIL IN BENDING

* IN THE ABOVE EXAMPLE PROBLEM THE OEADMAN DEPTH IS 5 FEET. THE SLOPE RATION IS 1-4 AND THE CABLE IS 3/4 INCH IPS A 14-INCH TIMBER IS USED WITH A 14 FOOT LENGTH AND 10 1/2-INCH THICKNESS

/■'igure NttmnRraph "A."

165

166

DESIGN OF FLAT BEARING PLATES FOR RECTANGULAR DEADMEN DIAM OF CABLE IN INCHES THICKNESS OF BEARING PLATE IN INCHES (X)

PS MPS ?,6 V'/,6'3/'6 ’Z« 1 1% IX 7 ^ 2% 1-1%

1%

V/:

« IK

sS IK 1'^

l/A

1/8 \<0 ßtP'

-f\Ni 1%

7/t

7/» TV 7/8 19

TVaS 5/8

BP S/B 5/B

3/8

-W- 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 d LENGTH OF BEARING PLATE IN INCHES (Y)

SAMPLE PROBLEM: ENTERING THE GRAPH AT %" IPS CABLE WITH A 14"

DEADMAN IT SHOWS THAT A THICK AND 8" LONG BEARING PLATE

IS REQUIRED. Figure 6 -14 Nomograph "B. "

DIAM. OF CABLE IN INCHES

IPS PS MPS

1!4

36" 30"

LOG LOG 24" (d) 20" .5d

'4?

/18

T

1 T/4 16

IÎ4

ÇO' 114 .A 14 v5

// T /■A 114

a//« / A -HKX d V/i

Z i ns

fJîA; -»|.5d o- 10"

V 8"

6" 1/2 1/2

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 1

LENGTH OF BEARING PLATE IN INCHES (

NOTE: THICKNESS OF BEARING PLATE IS DETERMINED BY FIRST CURVE TO

THE RIGHT OF CABLE SIZE/DEADMAN HEIGHT INTERSECT

Figure 6-15. Nomograph “C

< <

o

168

CHAPTER 7

FIXED BRIDGES

Section I. NONSTANDARD BRIDGE DESIGN

7-1. NOMENCLATURE

a Superstructure. The load—carrying component of the superstructure is the stringer system, which may be rectangular timber, round timber, or steel beams (figs. 7—1 and 7- 2).

b. Substructure. Intermediate supports for the superstructure may be timber bents, timber piers, pile bents, or pile piers, or a combination of these supports (fig. 7—1 ).

7-2. NOTATIONS

A = Area (in^)

Ap = Bearing area of post or pile (in^)

b = Width of stringer (in)

bc = Width of corbel (in)

bCap = Width of cap (in)

bjin = Width of sill (in) BpL = Width of bearing plate (in)

d = Total depth of stringer (in)

dc = Depth of corbel (in)

dcap = Depth of cap (in) Dp = Diameter of pile (in)

H = Height of timber bent post (ft)

Hp = Distance from fixed point to point of lowest bracing

Hm = Max height of post (ft)

DL

LL

kip = 1000 lbs

L = Span length (ft)

Lc = Effective corbel length (ft)

Le = Effective span length (ft)

Lfjg = Length of footing (in)

Lm- = Max span length (ft)

Lp[_ = Length of bearing plate (in)

Mni = Dead load bending moment for entire span (kip—ft)

= Live load bending moment per lane (kip- ft)

= Total bending moment per stringer (kip—ft)

= Total moment acting on the corbels

= Dead load bending moment per stringer (kip—ft)

= Live load bending moment per stringer (kip—ft)

= Number of braces

= Number of corbels

= Number of lanes

= Number of posts or piles

= Theoretical number of piles required

Ns = Number of stringers

N^ = Effective number of stringers per lane

N2 = Effective number of stringers per lane for a 2—lane bridge

0 = Diameter of pile (in)

Pjj = Capacity per pile based on end—bearing support

Pf = Capacity per pile for friction support

Pj = Total design load on substructure (kips)

S|j = Maximum spacing of bracing (ft)

Sx = Center to center spacing of component "x" (ft)

tp|_ = Thickness of bearing plate (in)

M

m

Mc mDL mLL Nb N.

Pr

169

170

Vc = Total shear acting on the corbels vc = Shear capacity of one corbel

VDL = Dead load shear for entire span (kips) V|_|_ = Live load shear per lane (kips)

v LL = Total shear per stringer (kips) VQ|_ = Dead load shear per stringer (kips) V|_|_ = Live load shear per stringer (kips) Wp = Width of roadway from inside curb to inside curb (ft)

W<j = Width of concrete slab (ft)

ROUND OFF RULE: Round the value down to the nearest whole number if the decimal is 0.09 or less, otherwise round up. Use this rule throughout where noted with an asterisk (*).

7-3. SUPERSTRUCTURE DESIGN (Timber and Steel Stringers)

a. Stringer Selection and Design. (1 ) Step 1 : Determine the maximum span length, Lm, of the stringers

available from table 7—1 or table 7—2. Choose only those stringers with an Lm value ¿ the span length.

NOTE: Designs computed in this chapter are not conservative.

(2) Step 2: Determine the number ofrequired stringers: WR

* Ns = ~ + 1 (Minimum Ns = 4)

Determine the center-to-center stringer spacing: WR

Ns-1 (Do not round off)

riACCMCNT CONTROL LINKS„ CURS AND

CURS RISER

HANDRAIL

TREAD Cf

m m. 2nd SEAN

TRANSVERSE SRACINO

SIU

f OOTINO

DECKINO

!•» SEAN TIMSER STRINGERS

LATERAL SRACE

rosT

sreci STRiNocis CAP

Figure 7-1. Timber trestle bridge.

0 —

7\ >v\ FLANOE

WEB

(Tinib (IU«I Crett-tnctlon)

Figure 7—2. Stringer dimensions.

Table 7—1. Properties of Timber Stringers

ACTUAL

SIZE

(b x d)

(in)

(a)

MOMENT

CAPACITY

m

(kip ft)

(b)

SHEAR

CAPACITY

v

(kipi)

(c)

MAXIMUM

SPAN

LENGTH |Lm)

(ft)

ACTUAL

SIZE

(b x d)

(a) MOMENT

CAPACITY

m

(kip-ft)

(b)

SHEAR

CAPACITY

v

(kipt)

<0

MAXIMUM

SPAN

LENGTH (L^

(ft)

* 4x 10

•4x12

6x8

6x 10

6x12

* 6x 14

* 6 x 16

* 6x 18

8x8

8x 10

8x12

8 x 14

6x 16

•8x18

* 8x 20

•8x22

* 6x 24

10 x 10

10 x 12

10 x 14

10 x 16

10 x 18

10 x 20

* 10 x 22

MOx 24

12 x 12

8 53

13 33

19 20

1280

20 0

28.6

39 2

51 2

64.8

17 07

26 7

38 4

52 3

68.3

86.4

1067

129.1

153.6

33.3

48 0

65 3

853

108.0

1333

161 3

192 0

57 6

3.2

4.0

4.8

4 8

6.0 7 2

8.4

96

10 8 6 4

80

9.6

11.2 12.8 14.4

16.4

17.6

19.2

10 0

12.0

14.0

16 0

18.0

20.0 22.0

24.0

14.4

9.5

11.9

14.3

95

11.9

14.3

16.7

19.1

21 5

9 5

11.9

14.3

16.7

19.1

21.5

23.8

26 2

26 6

11.9

14 3

16.7

19.1

21.5

23.8

26.2

26.6

14.3

12x20

12x22

12 x 24

14 x 14

14 x 16

14 x 18

14x20

14x22

14 x 24

16 x 16

16 x 18

16x20

16x22

16x24

18 x 18

18 x 20

18 x 22

18 x 24

8«

9ö

10^

11ÿ

120

130

140

160

180

160.0

193.6

230

91.5

119.5

151 2

186 7

226

269

136.5

172.8

213

258

307

194.4

240

290

346

10.05

14 31

19.63

26 1

33.9

43.1

539

24.0

26.4

28 8

19.6

22.4

25.2

28.0

30 8

33 6

256

28.8

32 0

35 2

38.4

32.4

36 0

39 6

43.2

5 7

7 2

8.8 10.6 12.7

15.0

174

22 6

28.6

23 8

26.2

28.6

167

19.1

21.5

23.8

26.2

28.6

19 1

21.5

23 8

26.2

28.6

21.5

23.8

26.2

28 6

9.5

10.7

11.9

13.1

14.3

15.5

16.7

19.1

21.5

KEY TO SYMBOLS

$ DIAMETER

• LATERAL BRACING REQUIRED AT MID POINT AND ENDS OF SPAN.

(a) FOR RECTANGULAR STRINGER NOT LISTED, m « W2 . FOR ROUND STRINGER NOT

LISTED, m-.02da 50

(b) FOR RECTANGULAR STRINGER NOT LISTED. ¥ = FOR ROUND STRINGER NOT LISTED, v» 09d* 10

(Ü FOR STRINGER NOT LISTED, L - M9d

Table 7—2. Properties of Steel Stringers

NOMINAL SIZE

ACTUAL DEPTH

<d) {in)

ACTUAL WIDTH

(b) (in)

FLANGE THICKNESS

«fi (in)

WEB THICKNESS

«w> (in)

MOMENT CAPACITY

(kip-ft)

MOMENT CAPACITY

(kips)

MAX SPAN LENGTH

<■-«,> (ft)

MAX BRACING SPACING

(ft)

51BU276

•39WF211

•37WF206

36WF300

36WF194

36WF182

36WF170

36WF160

36WF230

36WF150

•36WF201

33WF196

33WF220

33WF141

33WF130

33WF200

•31WF180

30WF124

30WF116

30WF108

•30WF175

•27WF171

27WF102

27WF94

•26WF157

51 1/4

39 1/4

37 1/4

36 3/4

36 1/2

36 3/8

36 1/8

36

35 7/8

35 7/8

35 3/8

33 3/8

33 1/4

33 1/4

33 1/8

33

31 1/2

30 1/8

30

29 7/8

29 1/2

27 1/2

27 1/8

26 7/8

25 1/2

14

11 3/4

11 3/4

16 5/8

12 1/8

12 1/8

12

12

16 1/2

12

11 3/4

11 3/4

15 3/4

11 1/2

11 1/2

15 3/4

11 3/4

10 1/2

10 1/2

10 1/2

11 3/4

11 3/4

10

10

11 3/4

1 5/8

1 7/16

1 7/16

1 11/16

1 1/4

1 3/16-

1 1/8

1

1 1/4

15/16

1 7/16

1 7/16

1 1/4

15/16

7/8

1 1/8

1 5/16

15/16

7/8

3/4

1 5/16

1 5/16

13/16

3/4

1 1/4

3/4

3/4

3/4

15/16

13/16

3/4

1 1/16

11/16

3/4

5/8

3/4

3/4

13/16

5/8

9/16

3/4

11/16

5/8

9/16

9/16

11/16

11/16

1/2

1/2

5/8

3067

1770

1656

2486

1492

1397

1302

1217

1879

1131

1545

1433

1661

1005

911

1506

1327

797

738

672

1156

1059

599

546

915

594

450

425

520

431

406

381

365

421

350

402

377

392

313

300

362

327

273

263

255

304

282

217

205

237

133

100

95

94

93

93

92

92

91

91

90

85

85

85

85

77

76

76

75

70

15

15

15

25.5

14

13

12

115

19.5

10.5

16

17

20

11

10

18.5

16.5

11

10

17.5

18.5

10

173

174

Table 7-2. Properties of Steel Stringers (Con't)

NOMINAL SIZE

ACTUAL DEPTH

(d)

(m)

ACTUAL WIDTH

(b)

(m)

FLANGE THICKNESS

«V (in)

WEB THICKNESS

(in)

MOMENT CAPACITY

(kip-ft)

MOMENT CAPACITY

(kips)

MAX SPAN LENGTH

<Lm> (ft)

MAX BRACING SPACING

<Sb> (ft)

24WF94 24WF84 24WF100 241120 241106

24180 24WF76

•24WF1S3 *241134 *22175

•21WF39

*211112

21WF73 21WF68 21WF62

20185 *20165 •20WF134

18WF60

*18186

18WF50 18155

•18WF122

24 1/4 24 1/8 24 24 24

24 23 7/8 23 5/8 23 5/8 22

21 5/8 21 5/8 21 1/4 21 1/8 21

20 20 19 5/8

18 1/4 18 1/4

18 1/8 18 18 18 17 3/4

12

8

7 7/8

11 3/4 8 1/2 7

11 3/4 7 7/8

8 1/4 8 1/4 8 1/4

7 1/8 6 1/2

11 3/4 7 1/2

7 1/2 8 7 1/2

6 11 3/4

7/8 3/4 3/4

1 1/8 1 1/8

7/8 11/16

1 1/4

1 1/4 13/16

1 3/16

1 3/16 3/4 11/16 5/8

15/16 13/16

1 3/16

11/16

5/8 15/16 9/16 11/16

1 1/16

1/2 1/2 1/2

1 3/16 5/8

1/2

7/16 5/8

13/16 1/2

5/8 3/4

1/2

7/16 3/8

11/16 7/16 5/8

11/16

11/16

3/8 1/2 3/8 1/2 9/16

497 442 560 564 527

391 394 828 634 308

495

338 315 284

337 245 621

243

326

220 292 200 199 648

191 174 173 286 224

183 163 217

283 168

238 148 140 130

195 132 177

115 184

108 133 99

126 145

62 61 61 61 61

61 61 60 60 56

55 55

54 54 53

51 51 50

46

46

46

46 46 46

11

9.5 13 12.5 12

85 8.5

20.5 15 8.5

24.5 14 5 9.5

23 5

9.5

13

8.5 14 8 7.5

23.5

Table 7-2. Properties of Steel Stringers ( Con't)

NOMINAL SIZE

ACTUAL DEPTH

(d)

(in)

ACTUAL WIDTH

(b)

(in)

FLANGE THICKNESS

<t,i (in)

WEB THICKNESS

(«J (in)

MOMENT CAPACITY

(k¡p*ft)

MOMENT CAPACITY

(kips)

MAX SPAN LENGTH

U-m» (ft)

MAX BRACING SPACING

(ft)

*18162 *18177

16WF112 *16170

16WF50

16WF45 16WF64

16WF40 •16150

16WF36

•16WF110 •16162 •16145 •15WF103

15156

15143

•14WF101 •14140

14151 14170

•14157

•14140 14WF34 14WF30

•14WF02

17 3/4

17 3/4 16 3/4 16 3/4 16 1/4

16 1/6 16 16 16 15 7/8

15 3/4 15 3/4

15 3/4 15 15

15 14 1/4 14 1/4 14 1/6 14

14 14 14 13 7/8 13 3/8

6 7/8 6 5/8

11 3/4 6 1/2 7 1/8

7 8 1/2

11 3/4 6 1/8 5 5/8

11 3/4 5 7/8

5 1/2 11 3/4 5 3/8 5 5/8

5 1/2 6 3/4 6 3/4

11 3/4

3/4 15/16 1

15/16 5/8

9/16 11/16 1/2 11/16

7/16

1

7/8 5/8

15/16 13/16

5/8 15/16 3/8 3/4

15/16

7/8 5/8 7/16 3/6 7/8

3/8

5/8 9/16 5/8 3/8

3/8 7/16 5/16 7/16 5/16

9/16 9/16 7/16 9/16 1/2

7/16 9/16 3/8

1/2 7/16

1/2 3/8 5/16 1/4 1/2

238 281 450 238 181

163 234

145 155 127

345 200 150

132 344 119

150 204

153 121 109 94

297

100 163 136 146 94

106 75

105 74

127 129 104

121 110

93 114 83

104 87

101 78 61

45 45 42 42

41

41 40 40 40 40

40 40 40 38

38

38

36 36 35

35 35 35 35 34

95 11.6 23.5 12

9

8 12.5 7.5 8.5 6.5

25 11.6

7.5 24.5

10.6

7.5 26

8 10

18

12.5 8 7.5

175

176

Table 7-2. Properties of Steel Stringers (Con U)

NOMINAL SIZE

ACTUAL DEPTH

<d)

(in)

ACTUAL WIDTH

(b)

(in)

FLANGE THICKNESS

«fi (in)

WEB THICKNESS

(O (in)

MOMENT CAPACITY

(kipl-ft)

MOMENT CAPACITY

(kips)

MAX SPAN LENGTH

(Lm)

(ft)

MAX

BRACING SPACING

(Sb>

(ft)

•14146 •13135 •13141

12WF36

•12165

12WF27

12150 12132 j

•12134 /

•11WF76

•10129 10WF25

•10140 10135 10125

10WF21 •10WF59 •9125 •9150 ■8135

•8128

8WF31 •8WF44

•7WF35 •6WF31

13 3/8

13 12 5/8 12 1/4 12

12 12

12

11 1/4 11

10 5/8

10 1/8 10 10 10

9 7/8 9 1/4

9 1/2

8 7 7/8 7 1/8

6 1/4

5 3/8

5 5 1/8

6 5/8

6 1/2 5 1/2

5 4 3/4

11

4 3/4

5 3/4

6 5 4 5/8

5 3/4

9 1/2 4 1/2 7 6

7 7/8 7 1/8

6 1/4

11/16 5/8

11/16 9/16 15/16

3/8

11/16 9/16

5/8 13/16

9 '16

7/16 11/16

1/2 1/2

5/16 11/16 1/2 13/16 5/8

9/16

7/16 5/8

9/16 9/16

1/2 3/8 9/16 5/16 7/16

1/4

11/16

3/8 7/16

1/2

5/16 1/4

3/8 5/8 5/16

1/4 7/16 5/16 3/8 5/16

5/16

5/16 3/8 3/8

3/8

108 103

182

76

113 81

81 202

67

59 92 65 55

48 132

51 103

49 61 81

99 72

104 56 73

120 62

72 77

48 38

53

36 56 43 45 34

35

33 40 37

31

34

33 32 31 30

30 30 30

28 28

27

25 25 25 25

25 23

24 23 20

20

20 20

18 16

9 8 95

9.5 21

10 75

8.5 27

8.5 8

14

8 75

6.5 23

8 21

15.5

11.5 14.5 21

18.5 18.5

•THESE NOMINAL SIZES HAVE NO U.S. EQUIVALENT.

FOR STRINGERS NOT LISTED:

m • 2.25^«^+8,^6)

v « l&SldjXtJ

(3)

(4)

Step 3: Determine the effective number of stringers for one wa> (N-|) and two-way (N2) traffic: (For a one—way bridge compute only N j.)

5 N1 = _ +1 (Do not round off)

N2 = Vs Ns (Do not round off)

Use smaller of N.| or N2 for all further calculations.

Step 4: Determine the live load moment per lane, from figure 7- 3. Calculate the live load moment per stringer, muJ

Timber Stringer

Steel Stringer

_MLL m*-*- N1 or N2

1.15 (Mll) m « » =

LL Nj or N2

(5) Step 5: Determine the dead load moment, MDL, for the entire span from figure 7- 4. Calculate the dead load moment per stringer (UIQ^):

mDL=

M

N

DL

s

(6) Step 6: Calculate the total moment required (mp|EQD) per stringer: mREQD = mLL + mDL Compare the total required moment (mp^Qp) with the

, moment capacity (m) of the desired stringer found in table 7—1 or table 7- 2. (a) If the moment capacity (m) is greater than the total required moment (mREQD>, a moment failure will not occur. Proceed to Step 7. (b) If the moment capacity (m) is less than the total required moment (mpEQp), add one stringer and return to Step 2 or select a stringer with a moment capacity greater than the required moment.

177

LIV

E L

OA

D B

EN

DIN

G M

OM

EN

T,

ML

L,

IN K

IP F

T P

ER L

AN

D,

178

5000 4000

3000

2000

/ 1000 z il

éZi & 'i 500

'ñ 400

300

200

100 5:

10 15 20 25 30 40 50 60 70 80 90 LENGTH OF SPAN IN FEET

Figure 7-3 Live load moment graph.

UV

E

LO

AD

SH

EA

R

PE

R

LA

NE

, V

. .

, IN

KIP

S

200

33 ISO o'**

160 O' \0 140

120 ms:: Ov 100

60?

80

AO ' AOV 60

301 50

30W

40 20

30 16 ( =

20 20 30 40 50 60 208090

LENGTH OF SPAN IN FEET

Figure 7-5 Live toad shear graph

181

182

(10)

(11)

For an unlisted steel stringer: v= 16.5(0^)

For an unlisted timber stringer: v^bd

10 Where: d = depth of stringer b = width of stringer tw = thickness of web

Step 10: Determine the number of lateral braces required between adjacent stringers: Timber: Determine if braces are required from table 7—1. Minimum lateral bracing material is 3" by Vkl of the stringer. Steel: Lateral braces are always required with steel stringers. Space braces along span length evenly. Minimum bracing materials is Vs" by Vid of stringer.

number braces: =-L + l Sh

Step 11: Bearing plate design (fig. 7—6) required for all steel stringers (not required for timber).

PL ~ bcap

3PL: 2(v / REQD (Round up to nearest whole inch.)

LPL

NOTE: Minimum Bp|_ = stringer flange width

lPL :

BpL - 2.5

8.48 (Round up to nearest Vs")

STEEL »EAKINO PLATE

' PL

f STEEL STKINOEft

L

B •! ■—S^- TIMBER CAP

Figure 7-6. Bearing plate.

b. Decking, Treadway. Curbing, and Handrail Design. Step 12: Determine the required decking thickness from the

decking chart, figure 7—7, using the design class and the stringer spacing in inches. Add two inches to the required thickness if two or more layers of plank decking are required. (Two inches is added only ONCE regardless of number of layers stacked.) Absolute minimum decking thickness is 3 inches. For treadway, use at least 2—inch material. For curb and handrail design, see figure 7-8.

183

184

t/> UJ X u z z l/) to UJ

Z

u X ♦— O z u UJ O

20 30 40 90 90 72

STRINGER SPACING IN INCHES

Figure 7— 7. Decking chart.

2-0

2”X4,a HANDRAIL

4"X4" HANDRAIL POSTS

2>*X4" KNEE-BRACES

6"X6" CURBING

6"X12" CURB RISERS

TREADWAY (Bp D*«ign)

r=yj

^ DECKING (By D«ilgn)

(Extend •'fry 5th d*<k plonk)

Figure 7—8. Handrail and curbing.

7—4. SUBSTRUCTURE DESIGN (intermediate Supports)

a Timber Trestle Bern Design (fig 7—9).

DRIFT PIN

TIMBER CAP

2" SCABBING

TIMBER POST

3" TRANSVERSE

BRACING

TIMBER FOOTING

^TIMBER SILL

Figure 7-9. Timber trestle bent.

(1) Step 1: Determine critical support by finding the effective span length (Le) for each intermediate support: Le = Li + 1-2 (sum of adjacent span lengths) The support for which l_e is the greatest will be the critical support, which must be designed.

(2) Step 2: Check the post height (H) of the tallest support against buckling. Post must be chosen from materials available (minimum post size is (6 in. x 6 in.) Find the maximum post height (Hm) in table 7—3.

> H, buckling will not occur. Use horizontal braces at midpoint, or select a larger post if Hfp <H.

NOTE: All bracing on intermediate supports should be bolted to posts, cap, and sill.

185

186

Table 7—3. Properties oj Timber Posts

Size of Post (in)

6x6

6x8

8x8

8x 10

10 x 10

10 x 12

12 x 12

Capacity per Post

(kips)

18

24

32

40

50

60

72

Max. Height

(ft)

15

15

20

20

25

25

30

Size of Pile (in)

8.{>

94»

10*

11*

12*

13*

14*

Capacity Per Pile (kips)

25

32

40

47

56

66

76

Max. Height (ft)

18

20

22

25

27

29

31

(3)

(4)

(5)

Step

Step

Step

3: Determine the design load acting on the critical support: (a) Using the design class and l_e, determine the live load shear per lane (VnJ from figure 7—5.

(b) Using the adjacent span lengths, L1 and L2

separately, and the type of superstructure involved, determine the dead load shear (VDL) from figure 7-4. (c) Using the number of lanes (NL), the live load shear per lane (V^L), and the dead load shear (VDL), compute the total design load, Pj: PT = VLL(Nl) + VpL (in kips)

4: Determine the maximum load that one post can support, "capacity per post", from table 7-3.

5: Determine the number of posts required (Np) and the center—to - center post spacing (Sp):

•N = ! H capacity/post

Wo x 12

Np — 1

(Note: For a pier use ViPj.)

(inches)

(6) Step 6: Check maximum allowable center- to-center spacing of posts:

: 5 *dcap* ('nchest max Sp :

If max Sp ¿ Sp, add posts until max Sp> Sp or use a cap with a larger dcap dimension.

NOTE Absolute minimum size cap and sill is 6 inches by 8 inches.

(7) Step 7: Using the available footing material thickness in inches and the soil-bearing capacity of the soil on which the footing is to rest (table 7-4), determine the "K" value from figure 7—10. Then calculate the maximum allowable footing length, max Lftg: max L^g = k + bs¡|; (inches)

Tabic 7-4 Soil-Bearing Capacity

TYPE SOIL - SBC (kipt/lqlt)

Hardpan overlaying rock 24

20 Very compact sandy gravel

Loose gravel and sandy gravel compact sand and gravelly sand, very compact sand-tn- organic silt soils 12

10 Hard dry consolidated clay

Loose coarse to medium sand, medium compact fine sand

Compact sand clay

Loose fine sand, medium compact sand-inorganic silt soils

Firm or stiff clay

Loose saturated sand-clay soils, medium soit clay

187

188

60

50

40

FOOTIN G I THICKNESS*" 30

4” 20

2 4 6 8 10 12 14 16 18 20

SBC (kips/sq. ft.)

Max LFTG= K + bs|Ll

MINIMUM WIDTH OF FOOTING 12"

Figure 7—10 Fooling chart.

(8) Step 8: Using the soil—bearing capacity, (SBC in kips/sq ft) and the ground contact area of one footing (GCA in sq ft), compute the capacity of one footing. Capacity/footing = (GCA)(SBC) (kips)

(9) Step 9: Determine the number of footings required (Nftg) and the center—to—center footing spacing (SftQ):

•N. PT

''ftg capacity/footing

NOTE For a pier use 'APj

WR(12)

^FTG (N FTG - 1) (inches)

NOTE. Minimum number of footings is equal to the number of posts.

b Timber Trestle Pier Design Design of a timber trestle pier is identical to the design of a timber trestle bent EXCEPT that each bent Is designed for one-half the total load. Therefore, use 'APj in paragraph a, step 5, and step 9. A timber trestle pier, as shown in figure 7—11, will be used when loads are too great to be carried by a single bent or span lengths are greater than 25 feet. In addition to the nine design steps followed for the design of each bent, a common cap and corbel design must be made for a pier.

^0

COMMON CAP

CORBEL

DRIFT PINS

CAP

SCABBING

LONGITUDINAL BRACES

-POST

TRANSVERSE BRACE

Figure 7- l /. Timber trestle pier

(1) Step 1 through Step 9. For cap, sill, posts, and footing design for bents, see paragraph a.

(2) Step 10: Determine the effective corbel length (Lc): l_c = effective corbel length

NOTF Minimum l_c = 1/6Hp or 1/6 H

189

190

(3) Step 11: For design of corbels, check ratic of corbel length (l_c) to depth of corbel (dc) to determine if moment or shear governs.

*-c If < 12, shear governs, proceed to step 13

If—£ > 12, moment governs, proceed to Step 12

^c (4) Step 12: Determine the number of corbels (Nc) required for

moment by finding the total moment acting on the corbels (IVL) and the moment capacity of one corbel (mc).

(5)

(6)

P-riLc» M (ft-kips)

c 4 Determine mc for one corbel from table 7-1.

Mc N Proceed to Step 14

c mc Step 13: Determine the number of corbels (Nc) required for shear

by finding the total shear acting on the corbels (Vc) and and the shear capacity of one corbel (vc):

PT Vc =— (kips)

Determine vc for one corbel from table 7— 1.

Step 14: Determine the center- to- center spacing of the corbels based on the required number of corbels (Nc) as determined in Steps 12 cr 13.

WR(12)

Sr = c N_ — 1

(inches)

(7) Step 15: Determine the minimum depth of the common cap (dcap) and the minimum width of the common cap

(t>cap^

min dcap = 5

2 Pi min b.

CaP Ncbc

NOTE Absolute minimum size common cap is 6" x 8".

c. Pile Bent Design (fig. 7—12)

DRIFT PINS CAP

BOLTS

PILE

a

jj la

TRANSVERSE BRACING

Figure?—12. Pile bent.

NOTE. Pile type supports should be used instead of footing type supports when site conditions are affected by deep water or swift current causing scour, low capacity soil overlaying rock, or unconsolidated soil with low soil—bearing capacity.

191

192

(1) Step 1 through Step 3: Determine total load (Pj) on critical support (para a).

(2) Step 4: Determine the capacity per pile (P^) based on end—bearing support from table 7—3.

(3) Step 5: Determine the capacity per pile (Pj) for friction support from one of the following dynamic formulas for timber piles (formulas based on test pile data or static formula — use lowest value)

2(Wd)(h) Pi =

r (S+1.0)

2<Wd)(h) Pf = ' f (S + 0.1)

Double-Acting 2E

Pneumatic or Pi = Diesel <s + 0-1>

Static Formula Pf = 2 f( îrDpLg)

Wd = weight of druphammer (kips) h = average height of fall (ft) E = work energy of hammer (ft/kip) S = penetration of pile per blow for last 6 blows (inches/blow) f = friction coefficient from TM 5—312 Lg = length of pile in soil layer

(4) Step 6: Using the smaller of the two values obtained from Step 4 and Step 5 for the capacity per pile, determine the effective number of piles required (NDr):

PT N = (Do not round off)

P Allowable capacity pile

Drophammer

Single-Acting Pneumatic or Diesel

»

(5) Step 7: Determine the spacing to diameter of pile ratio (S_/Dp) to minimize a possible overlapping of pressure bulbs which can reduce the capacity of the piles:

Sp WR(12)

Dp=<NPr-1>DP

nR

N NOTE. For a pile PIER, substitute _£r for N

pr

If:—> 10 D/p

Each pile develops full capacity. Round Npr off and continue to Step 9.

DP

Use a pile pier design.

(6)

3 <_E <10 D_

Capacity is reduced due to pressure bulb overlap. Continue to Step 8.

Step 8: Determine the actual number of piles per row (Np) from the appropriate chart in figure 7—14, using Npr obtained in Step 6 and Sp/Dp Ratio obtained in Step 7.

NOTE: Minimum Np = 4.

(7) Step 9: Calculate actual center-to- center spacing of piles and check spacing limitations.

WR x 12 Actual Sr, (inches)

P (Np-1)

Minimum Sp = 3(Dp) (inches)

Maximum Sp = 5(dcap) (inches)

IF: Actual Sp <3(Dp) Return to Step 7 and design a pile pier.

193

194

IF: Actual Sp > 5(dcapS) Add more piles and check max and min spacing or increase depth of cap. Calculate new Sp/Dp ratio based on Np. Use appropriate

pile chart to obtain Npe using reverse procedure used for

V _£E=

Wr(12)-

Dp (Np-DDp

lf Npe^ Npr-°K

If Npe <Npr add 1 pile/row and repeat step 9 until Npe >

d. Pile Pier Design (fig. 7—13).

COMMON CAP

LONGITUDINAL

BRACE

✓ /

DRIFT PIN

CORBEL

BOLTS

Figure 7—13 Pile pier.

/

NU

MIS

R O

F P

IUS

RE

QU

IRE

D (N

pr)

\

(1) Step 1 through Step 3: Determine total load acting on the critical support (see para a).

(2) Step 4 through Step 9 (pile design based on spacing criteria): In Step 7 substitute %Npr for Npr and in Step 8 use the two—bent pile pier chart in figure 7--14 to determine the actual number of piles required per row (see parac).

12

11

10

9

8

7

6

5

4

3

4 6 8 10 12 14

NUMBER OF PIUS (Np)

(o) SINGLE BENT

20

I 4 6 8 10 12 14

NUMBER OF PUIS PER BENT (Np)

(b) TWO BENT PIER

Figure?—} 4 Pile charts.

195

196

(3) Step 10 through Step 15: Design common cep and corbel system (para b).

7- 5. SUBSTRUCTURE DESIGN

a See figures 7—15 through 7—18 and table 7—5 for selection of abutments.

b. Deadmun Design. For deadman design, see TM 5—312.

NOTE: If time does not permit a detailed deadman design, use at least 14” diameter deadman at least as long as the roadway width. It should be attached to the abutment with at least ten 3/8" diameter cables. The deadman should be buried 4' deep and placed 20' from the abutment.

NOTE- Pile piers should be used in low capacity soils where pile bents do not give the required support or in situations requiring greater stability due to span lengths, support heights, or available material size.

END DAM

ftEAl

HEEL

Figure 7-15. Concrete abutment

END DAM

CAP

WALE

Figure 7-16

Pile abut ment.

DEAD-MAN

á PILE

i

END DAM-

SILL,

FOOTING

üij

8

CABLE

Figure 7 -18.

Timber bent abutment.

f <V DEAD-MAN

«EilWIMJMRMMC

Figure 7-17.

Timber sill abutment.

END DAM

CAP

WALE

POST <k CA>le

SILL FOOTINO

ZQ cr,

197

198

Table 7--5 Abutment Selection Guide

TYPE HEIGHT SITE CONDITIONS DESIGN REMARKS

CONCRETE

ABUTMENT

TO 20' MOST PERMANENT TYPE

USE ON FIRM BANKS WITH GOOD SOIL.

FOR DESIGN, SEE TM 5- 312

TIMBER SILL ABUTMENT

TO 3' MOST ECONOMICAL AND EASILY CONSTRUCTED.

USE ON HIGH, FIRM BANKS WITH GOOD SOIL.

I DESIGN IS IDENTICAL TO TIMBER TRESTLE BENT WITHOUT POSTS.

Le CONSISTS OF SUPPORTED SPAN ONLY (PAR a).

TIMBER BENT

TO 6' USE ON FIRM BANKS WITH GOOD SOIL.

DESIGN IS IDENTICAL TO TIMBER TRESTLE BENT Le CONSISTS OF

SUPPORTED SPAN ONLY (PARA j) TO PREVENT OVERTURNING, USE DEADMAN

PILE ABUTMENT

TO 10' USE ON GENERALLY

SLOPING BANKS WITH

POOR SOIL CONDITIONS, WHEN STABILITY IS DE-

SIRED, OR WHEN BANKS FLOOD FREQUENTLY.

DESIGN IS IDENTICAL TO PILE BENT.

Le CONSISTS OF SUPPORTED SPAN ONLY (PARA cl. TO PREVENT OVER-

TURNING, USE DEADMAN

Sectionil. BRIDGE CLASSIFICATION

7- 6. TIMBER TRESTLE BRIDGE CLASSIFICATION

Bridge classification is based on the class of the superstructure only, since this is considered to be the controlling feature. However, the condition of both superstructure and substructure components should be examined closely for damage or deterioration and the probable effect on the bridge capacity.

(1) Step 1: Conduct a bridge reconnaissance to obtain the following information on the existing bridge: Roadway width (Wp) in feet Span length (L) in feet (critical span) Type, size, and number of stringers Type of decking and thickness of decking Number of lateral braces Condition of the components

(2) Step 2: Locate the stringer to be classified in table 7—1 or table 7—2 and determine the moment capacity (m) in ft—kips.

(3) Step 3: Obtain the dead load moment per span (Mp^) for the type superstructure involved from figure 7 4. (NOTE. If Wp > 18', bridge is 2—lane.)

(4) Step 4: Calculate the dead load moment per stringer (mpiJ using the actual number of stringers (Ns):

mDL = MDL

Ns (ft-kips)

(5) Step 5: Calculate the live load moment per stringer (mL|_) using the appropriate formula for either steel or timber stringers:

m • mDL

Steel :mLL=

Timber i m|_|_ = m — ^DL

199

200

Check the maximum span length (Lm) of the stringer from table 7—1 or table 7—2. If Lm > L, proceed to Step 6. If Lm <L, multiply m(_|_ by the ratio Lm/L to obtain a new and lower value of m|_|_-

(6) Step 6: Determine the effective number of stringers per lane for one-way traffic (N-|) and for two-way traffic (N2). (If WR > 18') by first computing the stringer spacing (Ss):

WR

S. = (feet) Ns—1

5 One- way traffic: Nj =-^ + 1

Two- way traffic: N2 = 3/8 Ns

(NOTE: DO NOT ROUND OFF N, or N2.)

For One-Way If N1 > N2 use N, If N2 > N^ use N^

For Two-Way If N^ > N2 use N2

If N2 > N-| use N,

(7) Step 7: Determine the live load moment per lane (M|_|_) using the value of m|_|_ obtained in Step 5 and N-j and/or N2

obtained in Step 6: MLL= N, (mLL^ (ft~k'Ps/lane)

(8) Step 8: Determine the classification of the bridge based on bending moment by entering figure 7-3 with M|_|_ end span length (L) for both wheeled and tracked vehicles.

NOTE If N1 > N2, return to Step 7 and calculate M|_L

using N2 in place of N-|. Another classification will be obtained from figure 7—3 which will give a class based on two-way traffic.

(9)

(10)

(11)

(12)

(13)

Step 9: Determine the shear capacity (v) of the stringer in kips from table 7—1 or table 7-2.

Step 10: Obtain the dead load shear per span (VQ|_) for the type superstructure involved from figure 7—4. Calculate the dead load shear per stringer (v0|_):

VDL ; 'DL

N, (kips per stringer)

Step 11: Calculate the live load shear per stringer (v|_|_) using values for v and VQ(_ obtained in Step 9 and Step 10: vDL = v - vDL (kips per stringer)

Step 12- Determine the live load shear per lane (VL(_) us'n9 I*16

appropriate formula for either steel or timber stringers: 2(VLL*

V|_|_ = -777- (kips per lane) Steel

Timber : V|_L =

1.15

JI6

3

N <VLL>

Step

(N, + 1)

13: Determine the classification of the bridge based on shear by entering figure 7- 5 with V|_|_and span length (L) for both wheeled and tracked vehicles.

NOTL: If Ni > N2, return to Step 12 and calculate V|_|_ using N2 in place of N^. Another classification will be obtained from figure 7—5 which will give a class based on two-way traffic.

(14) Step 14: Determine the maximum classification for both one -way and two- -way traffic based on the roadway width restrictions (Wp) (table 7—6).

Table 7—4. Minimum Roadway Width Requirements.

Bridge class 4 -12 13 -30 31 -60 61 -100

One-Lane 9'~0" IV-O" 13'-2" 14'-9''

Two-Lane 18'-0" 18'-0" 24-0" 27'-0"

201

202

(15) Step 15: Determine the decking class by first calculating the effective thickness of decking (teff) for the type of decking involved:

Laminated: teff = (tactual^% LarT1*

Plank. tsff - tactua| — 2

(NOTE Subtract 2" for mH/Z/Vaêred plank deck only.)

Using the effective thickness (teff) and the stringer spacing (Ss) in inches, obtain the decking class from figure 7—7.

(16) Step 16: Calculate the number of lateral braces required (N^) using the maximum spacing of bracing (S^) from table 7 -2 for steel stringers:

(17)

Steel : N _L S

1

Timber : = 3, If d > 2b for stringer

If necessary, add bracing as required before posting final bridge classification sign.

Step 17: Determine the final bridge classification by comparing the classes for moment, shear, two-way width, and deck, and then selecting the lowest critical class for each type crossing, wheeled or track.

Type Crossing TRACKED One-Way Two-Way

WHEELED One-Way Two-Way

MOMENT SHEAR WIDTH DECK

Step 1 Step 9 Step 14 Step 15

Step 8 Step 13

Final Class — choose lowest class for each type crossing

NOTE If the maximum one-way width class determined in Step 14 is less than either of the final one- way classifications, a width restriction sign indicating the maximum width clearance must be posted below the bridge class sign.

7 -7. REINFORCED CONCRETE BRIDGE CLASSIFICATION

Due to wide variations in design criteria, it is not possible to calculate the exact capacity of a reinforced concrete bridge based only on the measurable external dimensions. The class will be obtained by correlation to charts in TM 5-312.

Field measurements should be made on a concrete slab bridge as shown in Figure 7—19 and on a concrete T—beam bridge as shown in Figure 7—20, in order to classify the bridge according to TM 5—312.

W R

W R

WEARING SURFACE IF PRESENT (EXCLUDE FROM CALCULATIONS)

Figure 7-19. Concrete slab bridge.

203

204

W„

r^m LtddiimmmJ

Figure 7-20 Concrete T—beam bridge

7-8. MASONRY ARCH BRIDGE CLASSIFICATION

The masonry arch bridge is difficult to analyze for the purpose of obtaining a satisfactory military class. In order to classify a masonry arch bridge, make the necessary measurements as shown in figure 7—21 and follow the classification procedure as outlined and discussed in TM 5—312.

L

Figure 7-21 Masonry arch bridge.

Section III. STANDARD BRIDGES (BAILEY TYPE. M2. AND MEDIUM GIRDER BRIDGE)

7-9. PANEL BRIDGE, BAILEY TYPE. M2. GENERAL INFORMATION

a. The panel bridge, Bailey type, M2, is a through—truss bridge with the roadway supported between the two main trusses formed from 10-foot steel panels (fig. 7—22).

b. The engineer panel bridge company is the TOE unit designated to carry one bridge set and provide technical personnel and equipment to transport and supervise the erection of panel bridging.

c The bridge set contains components required to erect two 80—foot DS bridges or one 130-foot DD bridge. See tables 7—7 and 7—8.

d The cable reinforcement set for panel bridge M2 (Bailey type) increases to class 60 wheel and track, the classification of triple—single Bailey bridge for span lengths from 100 feet to 170 feet. For a span of 180 feet, the class is 50 wheel and 60 track. This system significantly reduces the assembly time and equipment necessary to cross class 60 traffic over spans of between 100 and 180 feet.

e. The cable reinforcement set consists of a system of cables attached to each end of the bridge and offset from under the bridge by posts. The cables are tensioned, causing the bridge to deflect upward. When a vehicle crosses the bridge, the bridge deflects downward, transferring part of the load into the cables.

7-10. SITE RECONNAISSANCE

Site reconnaissance should consider the following as a minimum: a Road net on which to transport equipment to the assembly area. b Approaches — a 150' straight approach, with a 10% slope or less, well

graded and drained, and permitting two—lane traffic. c Access roads — roads to and from the bridge capable of carrying

traffic for which bridge is required. d Abutments — check whether prepared or unprepared, assure equal

height. e Assembly areas — sufficient space for material stacking and bridge

assembly (fig. 7—23).

205

206 CRIBBING AND WEDGES UNDER .MIDDLE OF END TRANSOMS FOR ... -. -9 OR MO|)E U S. CLAS æ 3 Ei

) :

7 m

R 3 WEAR TREAD

REMOVED CHESS REMOVED

CLEARANCE BETWEEN TRUSSES 14U3"

CLEARANCE BETWEEN TRUSS GUARDS M'-l

-12-ó” ROAOWAY- FOOTWALK POST

SCO STEJL.RIBAND

GUARDRAILi

BASE PLATE

GRILLAGE

FOOTWALK

I BEARING

—5INGLÉ-H BAY. 1

RAMP

END VIEW (RAMP REMOVED)

h*»10‘ BAY TWO BAY RAMP-

CRIBBING AND WE DG ES UNDER MIDSPAN OF

RAMPS FOR U.S. CLASS 45 OR MORE

ELEVATION (FOOTWALK REMOVED)

Figure 7-22. Steel panel fixed bridge, Bailey Type, M2

Table 7- 7 Critical Dimensions o] Bailey Bridge

Road width betwpen steel ribands 12' 6"

Road width between timber truss guards 13' 9"

Lateral distance between centerlines of trusses

Inner trusses 14‘ 10”

Middle trusses 17' 10'*

Outer trusses 19' 3”

Lateral distance between centerlines of base plates

S truss bridge

0 truss bridge 1® ^

T truss bridge 17'3 1/2”

Lateral distance between outside edges of base plates

S truss bridge 19' 5”

D truss bridge 20' 11"

T truss bridge 21'IOl/2”

Lateral distance between measuring lugs of rocking roller IT 6 1/2”

templates

Lateral distance between measuring lugs of plain roller templates

SS, DS bridges

TS. DD, TD. DT, TT bridges

Longitudinal spacing between plain rollers

Height from base of base plate to top of chess

Height from base of rocking roller template to tup of

rocking roller

Height from base of plain roller template tu tup of plain

roller

Height from base of ramp pedestal to top of ramp chess

Height from bottom of half round lug under sloping end ul

ramp to top of ramp chess

Height from top of chess to overhead bracing

Normal

Expedient

Height from base of bearing to bottom of punel

Height from bottom of panel to top of chess

Height from bottom of half round lug of end post to tup

of chess

Height from base of rocking roller bearing to top of rucking

roller

11'6 1/2”

10'101/2”

25*

28 5/16"

16 5/16”

8 15/16”

17 1/4"

57/8"

14' 7”

12' 3”

5 17/32”

2011/16”

2213/3?”

207

208

Table 7-8. Weight per Bay of Bridge

CONSTRUCTION WEIGHT PER BAY TONS

BRIDGE

SS DS

TS DD TD DT TT

LAUNCHING NOSE SS DS DD

DECKING Stringers only

Chess and steel ribands

FOOTWALKS

OVERHEAD BRACING Supports, transoms, sway bracing, and chord bolts

WEAR TREAD AND TRUSS GUARDS

2.76 3.41

4.01

4.66

5.88

6.46 8.29

1.00 1.64

2.90

0.79

0.66 0.17

0.54

0.35

NOTE.' Footwalks. wear treads, and truss guards not included. Overhead bracing included on DT and TT.

JACKS ANO JACK SHOES

END POSTS

BRACING BOLTS, CLAMPS AND TOOLS

GRILLAGE

FOOTWALKS

RIBANDS AND RIBAND BOLTS

TEMPLATE

:G AP:

ÍSffira I cp BASE PLATE

p PLAIN ! • ' ROLLERS I

TEMPLATE! | I

-^zXtEja-

CHESS

TRANSOMS ON

PANELS

30’

STRINGERS

ll

25

RAMPS

30

SWAY BRACES

Figure 7- Suggested layout ot equtjunent at bridge site

,ÇÎ

+ 3

SO

NJO H

ION

ÍT]

fim A

f\n

n m

n i—

in

210

/. Turnaround — permit easy access to bridge assembly area. g. Equipment park — area large enough to hold all vehicles and close

enough to allow proper control.

7-11. BAILEY BRIDGE DESIGN

Design of the Bailey bridge is beyond the scope of this publication and is outlined in detailed in TM 5—277.

7-12. PLANNING DATA

Tables 7-9 and 7-10 contain crew size and breakdown and estimated assembly times for standard bridges.

7-13. SITE LAYOUT DATA

Site layout data is beyond the scope of this publication. It is outlined in detail in TM 5- 277.

7- 14. ASSEMBLY AND LAUNCHING DATA

Assembly and launch procedures are beyond the scope of this publication and are outlined in TM 5-277.

7-15. MEDIUM GIRDER BRIDGE

Data on the medium girder bridge was not available at the time of publication. It will be incorporated into a change when available.

Table 7—9. Organization of Assembly Crev

Truck driver Crane operator Hook man Panel carry

Pin

Transom-carry

Clamp

Brace, sway Raker

Frame

Chord bolt Tie plate

Overhead support Decking-stringer

Chess & riband

•* Total

Type of Bridge

SS DS TS DD TD DT

28 4

8

2

2

2 4

4

8 4

66

0/1 0/1 0/1

44/24 6/6

24/16 4/4

6/6

2/2

8/10 10/10

6/4

3/8 4/4

122/97

TT*

0/1 0/1 0/1

60/24

8/6 24/16

4/4

6/6 2/2

8/8 14/14

4/4

6/4

8/8 4/4

148/103

•First number indicates men required without crane, second if crane is used

• • All numbers reflect ideal number of men for each task.

211

212

Table 710 Assembly Tunes - Honrs

Length SS DS DT (3) TT {3)

40'

80' 2%

100' 274

6% 3% 574 7% 1174/1074

160' 674 8% 137«/1174 19/167« 1474/137« 2174/187«

24/207«

( 1 ) All times assume ideal conditions and footwalks omitted (a) Blackout - add 50 to 100 percent (b) Bad weather add 30 to 50 percent

Untrained troops - add 20 to 30 percent Example: (60'ss =V1:45> + (poor weather (50%) =0 52) + (untrained

troops (30%) 5 0.32) = 3.08 (3 hours, 8 minutes) (2) Times do not include site preparation. Add 1 to 4 nours, depending

on conditions. (3) Second number refers to construction using a crane

Section IV. MISCELLANEOUS BRIDGING

7-16. LIGHT SUSPENSION BRIDGE DESIGN

The suspension bridge (fig. 7-24) is used for long spans high above

obstacles. The floor system is suspended from cables, which are supported on towers and anchored to abutments.

a. Design Data See table 7—11 and figure 7—24.

neu met SP IK n = 4 lOIEI SUSPEIDEi

/ MtlK hl CIBLE

T IKCKSIir

7 n = 2

f» = l

p W1ÍVM SM ^7 DEADMIR

FLIORIEAHS V

STIIRSÍIS »V TOOfl IIACIHfi

h = EFFECTIVE SUSPENDER LENGTH

I s EFFECTIVE LENGTH OF CENTER SUSPENDER

n = PANEL POINT OF SUSPENDER

N = PANEL POINT OF TOWER

C = CAMBER

d = DIP

Figure 7-24. Light suspension bridge.

213

214

Table 7—11 Light Suspension Bridge Design Data

Item

Panel length

Data

10 to 15 ft.

Camber Approximately 2 ft.

Stringer design See paragraph 7-la.

4" x 4" for foot troops or pack animals.

6" x 6" for %-ton truck.

S** x 8" for %-ton truck.

Floor beams

Stress in suspenders Design for dead load of one panel, live load and 100%

of live load for impact. See table 11 -2for cable strength.

Length of suspenders h= L- (C + d)

Sag ratio 5% for foot bridges to 10% for animal and light vehicle

bridges.

Main-cable design

Sag ratio %

7 8 9

10 11 12 Va 16 Vs

Max total tension in

main cables, in parts of total suspended weight of bridge and load

1.94 1.57 1.46 1.35 1.23 1.12 0.90

Length of cable

between towers, in parts of span length

1.012 1.018 1.022 1.026 1.033 1.041 1.070

Towers 12" x 12" posts and caps will take loads, including a 2,/G*ton truck. 6" to 8" timber side, back, and fore- braces. '/?" wire-rope side and back guys. 1 to 1 slope for side guys; 2% horizontal to 1 vertical slope for back guvs.

Anchorage Deadman or other anchorage must hold maximum tension of main cable.

Factor of safety Wire rope = 2 Cordage = 3.5

b. Example—Main Cable Design. Determine tension in main cables for a 200 foot span suspension bridge with a suspended weight of 10 tons. Assume a 10 percent sag ratio and a 4 ton line load.

Maximum total tension in main cables for a 10 percent sag ratio = 36,000 x 1.35 = 48,600 pounds. If two main cables are used, each must have a tensile strength of 24,300 pounds.

7-17. THREE ROPE BRIDGE (fig. 7-25)

The three-rope bridge is used to carry personnel with full field packs, but it is limited to a maximum of 7 men at 5 pace intervals. Maximum length is 150 feet. For construction details see TM 5—270.

7-18. FOUR-ROPE BRIDGE

The four -rope bridge is used to carry pack animals and personnel. Maximum length is 100 feet. Maximum capacity is 5 men with full field packs spaced 5 paces apart or one pack animal with handler. See TM 5-270.

7-19. ARMORED VEHICLE LAUNCHED BRIDGE (AVLB)

The AVLB is used to trunsport vehicles up to class 60. The bridge is 63 feet long and requires 3 feet of bearing on each side of the gap-an effective length of 57 feet. The AVLB may be launched or retrieved from either side of the gap and employed without exposing the operators to fire. It is found in armored Bns (2ea) and Div Engr Bns assigned to armored Divs (4 launchers and 6 bridges).

Pounds

Suspended weight. Line Load Impact

20,000 8,000 8,000

Total 36,000

215

216

i

/Í1

1 4W at

—Jé

■

wl

m Vw._

Figure 7-25. Three—rope bridge.

7-20. M4T6 FIXED SPANS

Data is located in paragraph 6—2.

CHAPTER 8

CONCRETE CONSTRUCTION

8-1. COMPONENTS OF CONCRETE

Concrete consists of a binder known as cement paste (portland cement and water) and filler material called aggregate (sand and gravel).

a. Portland Cement Types. (1) Normal portalnd cement (Type I). This is used for all general

types of concrete construction, masonry units, and soil cement mixtures. Concrete made with Type I cement reaches its design strength after 28 days.

(2) High—early portland cement (Type HD. This is used where high concrete strength is required after a short curing period. Concrete made with Type III cement reaches its design strength after 7 days. Type III is used where it is desired to remove forms as early as possible, to put concrete into service as early as possible, and in cold weather construction to reduce the period of protection against low temperatures.

(3) A ir - e n t rai ne d portland cement (Types IA and ¡HA). Air—entrained cement increases the workability of plastic concrete and produces hardened concrete with greatly increased freeze—thaw resistance and watertightness. These air—entraining agents, which intentionally introduce minute air bubbles into the concrete mix, are recommended for all concrete construction. Air—entraining agents may also be added to the mix water at the job site.

NOTE' Storage of cement. As a minimum, cement bags should be stored on raised platforms with the top and sides protected by a waterproof covering.

h Mixing Water. (1) The purpose of water in the concrete mix is to combine with the

cement in the hydration process, coat the aggregate, and permit the mix to be worked.

(2) Mixing water should be clean and free from organic materials, alkalies, acids, and oil. In general, water that is fit to drink is suitable to mix with cement.

217

218

(3) Seawater may be used as mixing water with the understanding that the strength of the hardened concrete will be about 20 percent less than that mixed with fresh water.

c. Sand. The fine aggregate (sand) should be clean and free of salt, clay, or other materials which might coat the particles and impair binding of the cement paste.

d. Gravel. (1 ) Coarse aggregate (gravel) should be hard, durable, and clean. (2) The most economical concrete mix utilizes the largest gravel size

possible. Physical restrictions of the concrete structure, however, restrict the maximum size gravel to the following:

(a) one—third the depth of the concrete slab on grade. (b) one—fifth the thickness of the concrete wall. (c) three—fourths of the minimum clear space between reinforcing

steel or between reinforcing steel and the form.

8-2. CONCRETE MIX PROPORTIONING

a Mix Proportioning Mix proportioning is the selection of the most economical and practical combination of concrete components (cement, water, sand, and gravel) which will be workable in the plastic state and still develop the properties of strength, durability, and watertightness in the hardened state.

b. Water-Cement Ratio. (1 ) The water—cement ratio is expressed in gallons of water per sack

of cement. The water—cement ratio is of primary importance in mix proportioning in that the strength of the hardened concrete varies with this ratio. The lower the water—cement ratio, the higher the strength.

(2) Recommended water—cement ratios for concrete work follow: (a) Use 6 gal/sack for an average mix (b) Use 5 gal/sack for concrete placed under water, for concrete

used in a watertight structure, when seawater is used for mix water, and when air—entraining is used.

(3) Adjust the water—cement ratio for moisture in the sand. (a) Reduce ’/a gal/sack for damp sand (when squeezed in your hand,

if forms a ball yet leaves little moisture on your fingers).

(b) Reduce 1 gal/sack for wet sands, usually found after a rain or washing (forms a ball when squeezed in your hand, but leaves moisture on your fingers).

c. Slump. (1 ) Slump is a relative measure of:

(a) Workability of a concrete mix — the ease of placement of the plastic concrete and its resistance to segregation.

(b) Uniformity — a measure of similarity between batches made with the same mix proportions.

' (2) Procedure for determining the slump of a concrete mix is: (a) Obtain or construct a slump cone as in figure 8—1.

TAMPING ROD: DIA. — 5/8" LENGTH — 24'

4" DIA.

3 8" DIA

Figure 8—1. Measurement of slumps.

220

(b) Moisten the slump cone and place on a flat, level, moistenea surface.

(c) FIN the cone with plastic concrete in three layers, each layer consisting of approximately one—third the volume of the cone. As each layer is placed, it is rodded 25 times with a 5/8—inch diameter, bullet—pointed tamping rod. Each stroke of the rod should penetrate the layer of concrete below the layer being tamped, with the bottom layer being tamped its entire depth.

(d) When the cone is full, strike off the excess concrete level with the top of the cone.

(e) Carefully lift the cone from the concrete and place the cone beside the concrete pile. Place the tamping rod across the top of the cone and measure the distance between the bottom of the rod and the center of the concrete pile. This measured distance that the concrete has fallen is the slump.

(3) Recommended slump for general concrete construction is 3 inches. Where thin concrete sections are to be cast and where reinforcing steel is present in the structure, it is advisable to use high-speed vibrators in placing the concrete.

d. Sand and Gravel. Recommended quantities of sand and gravel to be used for mix proportioning are listed in table 8—1.

Table 8-1. Concrete Mixes

MAXIMUM SIZE GRAVEL TO BE USED (INCHES)

AGGREGATE - CUBIC FEET PER 1 SACK OF CEMENT

AIR-ENTRAINED NON-AIR-ENTRAINED GRAVEL

% inches

% inches

1 inch

1ft inches

2 in

1.9

1.9

1.8

1.8

1.6

2.0

2.0

1.9

1.9

1 9

1.5

1.9

2.1

2.5

2.7

e. Example Problem. Select mix proportion for a concrete footer using air—entrained cement (Type IA).

(1) Select w/c ratio (para 8—2b) - (w/c ratio = 6 gal/sack.) (2) Select slump (para 8—2c) - (slump = 3")- (3) Select aggregate (table 8—1).

(a) Determine the moisture condition of the sand. (Sand is checked and found to be damp.)

(b) Determine the maximum size gravel to be used. (Maximum size aggregate available is %'').

(c) Determine the type cement available, (air—entrained). (d) Mix proportions for a one—sack batch are: Water = 6 gal/sack minus 'A gal/sack = 5Vi gal/sack Cement = 1 sack air—entrained Sand = 1.9 cu ft Gravel = 1.9 cu ft (e) Mix the one—sack batch selected in (d) above and make a slump

test. If the slump measures less than 3 inches, mix a new one—sack batch using less sand and gravel. If the slump measures more than 3 inches, adjust the mix by adding sand and gravel to obtain the 3-inch slump. Never increase water content in an attempt to change a slump measurement. This practice changes the water—cement ratio, resulting in weakened concrete. When suitable proportions have been determined, convert the quantities of each material for the one—sack batch to those for a full mixer—size batch.

8-3. ESTIMATING AMOUNT OF MATERIALS REQUIRED

a Amounts of Materials. The amounts of cement, water, sand, and gravel to be ordered and delivered to the job site may be estimated according to the following steps:

( 1 ) Determine the volume of concrete needed in cubic feet. (2) Add a loss factor to compensate for handling losses. Add 10% for

projects requiring up to 200 cubic yards (5400 cubic feet) of concrete and 5% for projects requiring 200 cubic yards or more.

(3) Determine the total volume of loose, dry material (total cement, sand, and gravel) required. Multiply the volume of concrete (plus the loss factor) times 1.5.

222

(4) For estimating purposes, assume mix proportions of 1 part cement, 2 parts sand, and 3 parts gravel (1:2:3 = 6). Determine amounts of each material by multiplying the total loose volume (Step 3) by the proportional amount of the total mix:

cement = 1/6 x total loose volume sand = 2/6 x total loose volume gravel = 3/6 x total loose volume

(5) The amount of water needed may be determined by using a rule of thumb of 8 gallons of water per sack of cement. This amount will allow for mixing water as well as water used in curing and cleanup.

b. Example Problem. Determine the amounts of materials needed to construct a concrete wall measuring 10 feet long, 3 feet high, and 1 foot thick.

(1) Volume of concrete = 10 ft x 3 ft x 1 ft = 30 cu ft. (2) Add 10% loss factor (less than 200 cu yd).

(3) Volume of loose, dry materials = 33 cu ft x 1.5 = 49.5 = 50 cu ft. (4) Amount of each material required:

(5) Water = 8 gal/bag x 9 bags = 72 gal

8-4. ESTIMATING QUANTITY OF STORED AGGREGATE (fig. 8-2)

Aggregate is often stored in cone-shaped or tent-shaped piles. A good formula to estimate the volume of aggregate in a cone-shaped pile is: volume = 0.2618 x height x cone diameter squared. The volume of a tent—shaped pile is: volume = 0.2618 x (height x cone diameter squared) + .5 x height x (width x length of the linear section). The weight of the stored aggregate is determined by multiplying the volume by the unit weight of aggregate. A good estimate of the unit weight of aggregate is 100 Ibs/cu ft.

30 cu ft + 3 cu ft = 33 cu ft

Cement = 50 cu ft x 1 /6 = 8.3 = 9 cu ft (bags) Sand = 50 cu ft x 2/6 = 16.7 = 17cuft Gravel = 50 cu ft x 3/6 = 25 cu ft

CONE

m.

DIAMETER

TENT SHAPED PILE

l-*— LINEAR SECTION—»-J

V V/>TT/‘r'v -

" Jf Wl / /

& i i V X h#--. ■■■(■

n CONE /, CONE SECTION SECTION

Figure 8—2. Estimating quantity oj stored aggregate.

8-5. BATCHING

a. Once a design mix has been determined, lay out the site, placing the cement, sand, gravel, and water as close to the skip (load bucket) of the mixer as possible.

b. The gravel should be placed in the skip first, the cement next, and the sand last. The exact amount can be controlled by constructing measuring boxes which have inside dimensions of 1 cubic foot and then measuring all sand and gravel as it is placed in the skip. Water can be placed into the mixer either by the use of a metering device on the mixer or by hand.

c. The actual mixing time will depend on the method of discharge and size of batch. If discharge is directly into the form, the mixing time should be at least 1 minute for any mix. For a batch exceeding 1 cubic yard, the mixing time is increased 15 seconds for each additional V4 yard or portion thereof.

223

224

8-6. CONCRETE PLACING AND FINISHING

a Moisten the grade to prevent absorption of water from the mix. b. Oil all forms before placing concrete. c Wheel, shovel, or chute concrete into place—do not flow. Concrete

should not be allowed to free fall into forms from heights greater than 5 feet unless suitable drop chutes, baffles, or vertical pipes are provided. As concrete is placed, it should be compacted by vibrators, spades, or rods. Take care not to overvibrate.

d. Level and tamp into place with a strike- off screed. e. Delay wood floating for 30 to 40 minutes after the concrete is placed. /. Apply final steel troweling when thumb pressure barely dents the

concrete surface. Final troweling compacts the surface and leaves it smooth. g Start curing as soon as possible without marring the surface.

8-7. CURING

a. Curing is the procedure for preventing the- evaporation of mixing water from the surface of freshly poured concrete. Loss of water from the concrete will terminate, or at least limit, the chemical reaction (hydration) of cement and water. Since concrete will gain strength only so long as water is available to react with the cement, evaporation of this water will reduce the actual strength below designed strength.

b To obtain the designed strength, concrete made with Type I cement must be cured'(kept continuously wet) a minimum of 7 days. Concrete made with Type III cement must be cured a minimum of 3 days.

c Methods used to properly cure concrete depend upon the type of structure and may be accomplished by spraying or ponding, by covering with continually moistened earth, sand, burlap, or straw, or by covering with a water—retaining membrane.

d If spray-on curing compound is available, spray on the compound in one coat. Do not use the compound if the air temperature is above 100°F and the air is dry.

e. Do not let the temperature of fresh concrete drop below 40°F.

8-8.- FORMING

a Elements of Wooden Forms (figs. 8—3 and 8—4)

STUD 12*4 or 3*6 MAH)

SPREADER PUU WIRE

WA1E

STAKE

SHOE

TIE WIRE

(DOUBLE STRAND!

Figure 8—3. Form for a concrete wall

(1) Sheathing. Sheathing forms the surfaces of the concrete. It should be as smooth as possible, especially if the finished surfaces are to be exposed. Since the concrete is in a plastic state when placed in the form, the sheathing should be watertight. Tongue and groove sheathing gives a smooth watertight surface. Plywood or masonite can also be used.

(2) Studs. The weight of the unhardened concrete will cause the sheathing to bulge if it is not reinforced. Studs aré run vertically to add rigidity to the wall form. Studs are generally made from 2x4 lumber.

(3) Wales. Studs also require reinforcing when they extend over 4 or 5 feet. This reinforcing is supplied by double wales. Double wales also serve to tie prefabricated panels together and keep them in a straight line. They run horizontally and are lapped at the corners of the forms to add rigidity. Joints normally should be staggered to minimize weaknesses in form construction. Wales usually are made of the same material as the studs.

(4) Braces Bracing is usually required to maintain the vertical alinement of the forms and to resist movement during the concrete—pouring operation. Bracing is not considered a structural component in wall form design; i.e., it does not support the pressure of unhardened concrete.

225

226

Al— “rVV

Figure 8—4. Form for a concrete wall

(5) Shoe plates The shoe plate is nailed into the foundation or footing and is carefully placed to maintain the correct wall dimension and alinement. The studs are nailed to the shoe and spaced according to the wall form design.

(6) Spreaders. To maintain the proper distance between the two form sides, small pieces of wood (spreaders) are cut the same length as the wall thickness and placed between the forms. A wire should be securely attached to the spreaders so they can be pulled out from the top after the concrete has exerted its total pressure on the walls. The spreaders must be removed before the concrete hardens.

(7) Form ties (wire or tie rods). Ties resist the outward pressure of unhardened concrete. Where wire ties are used, a double strand is necessary.

(8) End walls (dams). Dams must provide the same strength as the sides of the wall form. Examples of end wall forming appear as figures—5. Note that wall thickness dictates the choice of end wall detail.

STUD. -SHEATHING

SHEATHING. WAIL

SPACING

f STUD WALES

END WALL END WALL (DAM) (DAM)

WALL THICKNESS GREATER THAN STUD SPACING

WAU THICKNESS LESS THAN OR EQUAL TO STUD SPACING

Figure 8—5. Recommended end wall (dam) details.

b. Wall Form Design. When more detailed form design methods are unavailable and 2x4 framing lumber is to be utilized (single 2x4 studs and double 2x4 wales), table 8-2 may be used as follows:

(1) Determine the rate of pour in feet per hour (the height of concrete being placed into the form per hour).

(2) Select the sheathing material to be used. (3) Read the center-to—center stud spacing in inches. (4) Read the center-to—center wale spacing in inches. (5) Select the column for the tie material to be used (8, 9, or 10 gage

wire or 3000--lb manufactured tie rods). Read, in inches, the maximum spacing of ties to be placed at each wale.

227

22

8

Table 8-2. Wall Form Design

MAXIMUM RATE OF POUR (FT/HR)

SHEATH MATERIAL

STUD SPACING

DOUBLE WALE SPACING

MAXIMUM TIE SPACING

8 GA 9 GA 10 GA 3000 LB TIE RODS

4',

5/8” Plywood

1"

Board

24" 17" 14"

16" 16" 25" 21"

IV

17"

27"

29"

5/8" Plywood

1"

Board

24-

12" 16" 12" 10"

15"

22"

12'

3/4" Plywood

1"

Board

2"

Board

16"

16" 7"

16" 12" IV 9"

15"

15"

20"

CHAPTER 9

MILITARY ROAD CONSTRUCTION

9-1. CROSS-SECTION OF A TYPICAL MILITARY ROAD (fig. 9 -1)

-MOTH OF CLEARING (ROADWAY + MIN OF 6 FT ON EACH SIDE)

ROADBED NTERCE DITCH

PTOR

ROADWAY

TRAVELED WAY

ORIGINAL GROUND

TRAFFIC LANE

1 CUT CROWN

DITCH

SHOULDER SURFACE COURSE

COURSE FILL

SLOPE

CUT SLOPE

DITCH SLOPE

Figure 9--¡ Typical cross section-illustrating road nomenclature

230

9-2. MINIMUM DESIGN REQUIREMENTS (table 9-1)

Table 9 -1 Militar} Road Specijications

Characteristics Specification

Width Traveled wav (single lane) Traveled way (two lanes) Shoulders (each side) Clearing

Min 11 5 ft (3 5 meters) Mm 23 It (7 0 meters) Mm 4 ft ( 1 5 meters)

Mm-6 ft (2 meters) on each side of roadway

Grades Absolute maximum

Desirable maximum

Lowest maximum gradabihty of vehicles for which road is built

Tangents and gentle curves, less than 6%, sharp curves, less than 4%

Horizontal curve radius Vertical curve length

Invert curves

Overt curves

Sight distance Non passing Passing

Desired min -150 ft (45 meters)

100- ft min (30 meters) for each 4% algebraic iMfurciici’s in gradifs

12b ft imn (40 mrlcrs) for each 4% algebraic difference in grades

Absolute mmimum -200 ft (60 meters) Absolute mmimum-600 ft (180 meters)

Load capacity Road proper Bridges

Sustain 18,000—lb single axle, dual wheel equivalent load

Accommodate using traffic

Slopes: Shoulders Crown (gravel and dirt) Crown (paved) Superelevation

Cut Fill

% to 1/4 in per ft

to % m per ft

% to 14 in per ft

% to 1 V* in per ft

Variable*) /Determined by soil types\ Variable^ Versus compaction /

Drainage Adequate crown or superelevation with adequate ditches and culverts in good condition Take full advantage of natural drainage Try to locate road at least 5 ft above the ground water table.

Miscellaneous- Overhead clearance Traffic volume Turnouts (single lane)

Min-14 ft (4 3 meters) 2.000 vehicles per day Mm-every % mile

9 3. CONSTRUCTION STAKES (fig. 9-2)

9-4. SOILS

a Soils Périment to Roads and Airfields (table 9—2).

b. Procedure for Field identification Tests of Soils (fig. 9—3).

STATION NUMBER 79*00

ALL CUT OR FILL SLOPES 1'/, = 1 DITCH SLOPE 3 -1

DITCH DEPTH 3 FEET

• Í2

SA¿-

l

1>4*9l =14 — +31» 13* iS>3

OFFSET STAKE ©

SLOPE STAKE

© © SHOULDER STAKE CENTERLINE STAKE

NORMALLY PLACED AT 100'INTERVALS

Figure 9—2. Diagram of construction stake placement and marking.

231

232

Table 9-2 Soil Characteristics

Symbol Description Drainage

Characteristics

Airfield Index

(Frost

Susceptibility)

Value as A

Subgrade

Value as A

Subbase

Value as A Compaction

Equipment

Gravels and

Sandy Gravel with little or

no Fines

Excellent

None to very

Slight

Good to

Excellent Good to

Excellent

Fair to

Good

Crawler Tractor, Rubber Tire

Roller, Steel

Wheel Roller

GM Silty Gravels.

Gravel-Sand

Silt Mixture

Fair to

Practically

Impervious

Slight to Medium

Good Fair to

Good

Not

Suitable

Rubber Tire

Roller.

Sheepsfoot Roller

GC

Clayey Gravels,

Gravel. Sand-

Clay Mixtures

Poor to

Practically

Impervious

Slight to Medium

Good Fair Not

Suitable

Rubber Tire

Roller,

Sheepsfoot Roller

Sands and Gravels,

Sands with little or no Fines

Excellent None to very

Slight

Fair to

Good

Fair to

Good

Poor to not

Suitable

Crawler Tractor,

Rubber Tire

Roller

SM

Silty-Sands,

Sand-Silt

Mixtures

Fair to

Practically

Impervious

Slight to

Medium

Fair to

Good

Poor to

Fair

Not

Suitable

Rubber Tire

Roller,

Sheepsfoot Roller

SC

Clayey Sands,

Sand-Clay

Mixtures

Poor to

Practically

Impervious

Slight to

High

Poor to

Fair Poor Not

Suitable

Rubber Tire

Roller,

Sheepsfoot Roller

Table 9-2. Soi! Characteristics (Continued)

Symbol Description

Drainage Characteristics

Airfield Index (Frost

Susceptibility) Value as A Subgrade

Value as A

Subbase Value as A

Base Compaction Equipment

Inorganic silts & very fine sand rock flour, clayey

silts with slight plasticity

Fair to Poor

Medium to High

Poor to Fair

Not Suitable

Not '

Suitable

Rubber Tire

Roller.

Sheepsfoot Roller

CL

Inorganic clays

low to medium Plasticity, gravelly or sandy clays

Practically Impervious

Medium to High

Poor to Fair

Not Suitable

Not Suitable

Rubber Tire Roller,

Sheepsfoot Roller

CH Inorganic clays

of high plasticity


Poor to Fair

Not Suitable

Not Suitable

Rubber Tire Roller, Sheepsfoot Roller

Mineral grains containing highly

organic matter

Poor to


Medium to High

Poor to Very Poor

Not

Suitable

Not Suitable

Rubber Tire

Roller, Sheepsfoot Roller

Peat and other

highly decomposed vegetable matter

Fair To Poor

Slight Not Suitable

Not Suitable

Not Suitable

Compaction not Practical

233

234

[ TAMPLE^ I

111) SEPARATE GRAVEL)

12) SEDIMENT TEST

i> Q - » PS S2 a S > z >» z

m O « a S

< o < O

135 figo 3 5

a NOTE: THIS PROCEDURE WILL GIVE A VERY HASTY

CLASSIFICATION OF SOILS, AND SHOULD NOT BE USED FOR DESIGN OF PERMANENT OR SEMIPERMANENT CONSTRUCTION.

Figure 9-3 Procedure, for field identification tests of soils.

(1) Separate gravel (a) Remove from the sample all particles larger than V diameter

(ä1 4 sieve). (b) Estimate the percent of gravel.

(2) ■ Sedimentation test to determine % sand. (This test eliminates

(a) Place the sample (less gravel) in canteen cup and mark the level with a grease pencil.

(b) Fill with water and shake the mixture vigorously. (c) Allow the mixture to stand for 30 seconds to settle out. (d) Pour off the water. (e) Repeat steps (b) through (d) until the water poured off is clear. (f) Dry the soil left in the cup (sand). (g) Estimate % sand by comparing the new level of sand with the

mark. % sand = total beginning volume of sample minus % gravel eliminated in paragraph (1) (b) above minus fines eliminated in (2) (a) thru (2) (f) above.

(a) Put approximately 1 " of the sample in a flass jar. (b) Mark the depth of the sample with a grease pencil. (c) Fill the jar with 5 to 6 inches of clear water. Leave 1" of air at

the top. (d) Shake the mixture vigorously (3 to 4 minutes). (e) Allow the sample to settle for 30 seconds. (f) Compare the sediment line with the grease pencil mark. (g) Estimate % sand settling to the bottom of the jar (by volume,

compare the sediment line with the grease pencil mark). % sand = total beginning volume of sample minus % gravel eliminated in (1) (b) above minus fines eliminated in (2) (a) thru (2) (f) above.

fines.)

METHOD ONE

OR

METHOD TWO

235

(3) Comparison of gravel, sand, and fines. (a) Percent of gravel was estimated in paragraph (1) (b) above. (b) Percent of sand was estimated in paragraph (2) (g) above by

either of two methods. (c) Percent of fines =100 minus % gravel minus % sand.

(4) Dry strength. (a) Form a moist pat 2" in diameter by Vi" thick. (b) Allow to dry with low heat. (c) Place the dry pat between thumb and index finger only and

attempt to break. id) If the pat breaks easily, it is silt (M). If the pat is difficult to

break, it is low compressible clay, (CL). If breakage is impossible, it is high compressible clay (CH).

(5) Powder Test. (a) Rub a portion of the broken pat with the thumb and attempt

to flake particles off. (b) If the pat powders, it is silt (M). If the pat does not powder, it

is clay (C). (6) Feel Test.

(a) Rub a portion of dry soil over a sensitive portion of the skin, such as the inside of the wrist.

(b) If the feel is harsh and irritating, sample is silt (M). (c) If the feel is smooth and floury, sample is clay (C).

(7) Shine test. (a) Draw a smooth surface, such as a knife blade or thumb nail,

over a pat of slightly moist soil. (b) If the surface becomes shiny and lighter in texture, the sample

is a high compressible clay (CH). If the surface remains dull, the sample isa low compressible clay (CL). If the surface is very dull or granular, the sample is silt (M) or sand (S).

(8) Thread test. (a) Form a ball of moist soil (marble size). (b) Attempt to roll the ball into a 1/8" diameter thread (wooden

match size). (c) If a thread is easily obtained, the ball is clay (C). If a thread

cannot be obtained the ball is silt (M).

(9) Ribbon test. (a) Form a cylinder of moist soil approximately cigar shape in size. (b) Flatten the cylinder over the index finger with the thumb, and

try to form ribbon 8 to 9 inches long, 1/8 to 1/4 inch thick, and 1 inch wide. (c) If an 8 to 9 inch ribbon is obtained the sample is high

compressible clay (CH). If the ribbon is less than 8 inches, it is low compressible clay (CL). If no ribbon can be obtained, the sample is silt (M) or sand (S).

(10) Grit, or bite test. (a) Place a pinch of the sample between the teeth and bite. (b) If the sample feels gritty, it is silt (M). If the sample feels

floury, it is clay (C). (11) Wet shaking test.

(a) Place a pat of very moist (not sticky) soil in the palm of the hand.

(b) Shake the hand vigorously and strike against the other hand. (c) Observe the rapidity of the water rising to the surface. If fast,

the sample is silty (M). If there is no reaction, sample is clayey (C). (12) Odor test.

(a) Heat the sample with a match or open flame. (b) If the odor becomes musty or foul smelling, this is a strong

indication that organic material is present. c. Determination of Optimum Moisture Content (OMC) To determine

whether or not a soil is at or near OMC, mold a golf ball size sample of the soil with your hands. Then squeeze the ball between your thumb and fore fingers. If the ball shatters into several fragments of rather uniform size, the soil is near or at OMC. If the ball flattens out without breaking, the soil is wetter than OMC. If, on the other hand, the soil is difficult to roll into a ball or crumbles under very little pressure, the soil is drier than OMC.

9-5. DRAINAGE

a. Ditches. (1) A triangular "Vee" ditch is normally used for relatively small

volumes of water. It is easily cut with the motorized grader.

237

238

(2) A trapezoidal ditch should be used where: (a) Large quantities of water are expected to be handled. (b) Fine-grained soils are present, and high water velocities (over 3

to 4 fps) will cause excessive erosion. (3) Minimum longitudinal slope for ditches is 0.5%, 2% preferred, and

4% is the maximum allowable without erosion controls. In fine-grained soils, erosion controls may be required in ditch slopes much less than 4%.

(4) In the absence of more detailed design, a good roadside ditch is a 2—foot--deep triangular ditch having slopes of 3:1 on the side adjacent to the roadway and 1:1 on the outside.

b Check dams. Check dams are used to slow the water and prevent erosion in ditches that have longitudinal grades of 2% to 8%. They may be made of timber, sandbags, concrete, rock, or similar materials. Figure 9—4 shows the method of computing check dam spacing.

c. Culverts. (1) General. Culverts are required wherever drainage channels are

needed to cross roads, io provide ditch relief, and to continue side ditches at the intersections of roads and access routes.

(2) Cross-sectional area (a) By field estimate method (Use for an area of 100 acres

that does not have a stream flowing through it.) Q = 2 ARC

Q = The volume of water in cubic feet per second 2 = A constant A = The area of the drainage basin in acres R = The design rainfall intensity based on the 1—hour, 2-year frequency rainstorm C = The ratio of runoff to rainfall

Step 1. "A" Area "What area is draining?” a. Delineation—Determining Area and Converting to Areas

(1) Use a topo map. (2) Locate the proposed drainage structure. (3) Confirm the location and topography by reconnaissance.

ROAD

WEIR NOTCH

L X Ji >- 1^ í'ü

rr-—ji:? 11

APRON

A = % GRADE OF CTNTERUNI Of »OAO A=7% %»»»«»*- ^ ■ —--

B = % ORAPE Of PROPOSED WATER SURFACE P~

f H R OLD DITCH GRADE —»-

SPACING IN PEET

100 H SPACING = ■

A- B H IS EXPRESSED IN FEET

Figure 9-4. Methods of computing check dam spacing

b. Method of Delineation on Topo Map. ( 1 ) Locate proposed or existing structures. (2) Locate the high points. (3) Draw flowlines from the high points perpendicular to the

contours. (4) Delineate (outline) the drainage basin.

239

240

c. Methods oj Measuring the Area by Use of a Map Scale (1) Stripper method (2) Planimeter method (3) . Geometric method (sum or rectangles and triangles) (4) Convert to acres (1 acre = 43,560 square feet)

Step 2. "R" Rainfall "How much rain can I expect?" Determine the 1 —hour, 2—year frequency rainstorm from the isohyetal

map. (inches hour). See figure 9--5. ( 1 ) Locate applicable geographic area. (2) If the area is close to an isohyet, select its value as "R". (3) If the area is between two isohyets, select the larger value as "R".

Step 3. “C" Runoff Coefficient "What ratio of water is going to run off?" a. Select one of the following values of "C":

(1) Impervious (asphalt, concrete, "tight" clay) = 1.0 (2) Pervious (well-graded gravel, beach sand) = 0.25 (3) All other = 0.5

b. Or refer to the "C" value, table 9—3.

Step 4. “Q" Runoff in Cubic Feet per Second (Q = 2 ARC) Step 5. Determine Cross-Sectional Area of Water

a. Q = AV b. A = Cross-sectional area of water in square feet c. V = Velocity, in feet per second; use 4 fps

Step 6. Culvert Design a. Slope should be 0.4% minimum to 2.0% maximum; use l 0%. b. Culvert design area = 2 x A (cross-sectional area of water). c Find the critical (minimum) fill depth (Fppjf,).

d. Compute the maximum pipe diameter (Dmax = 2/3 Fm¡n).

e. Select the maximum pipe diameter that can be used from table 9—4. f. Compute the most economical pipe size and number of pipes:

d. A =5. 4

Design area End area of one pipe from table 9- 4

100 120 140 160 00

i? BRITISH ISLES UNION OF SOVIET SOCIALIST REPUBLICS

CANADA 1 EUROPE

S.*" UNITED STATES CHINA

ASIAC^ JAPAN 1.6

MINOR ATLANTIC OCEAN

INDIA PACIFIC OCEAN MEXICOWEST INDIES

AFRICA

•s EAST INDIES

■ 2

2^* ki r u

0 ^ 2 2.5 SOUTH AMERICA

INDIAN OCEAN NEW

GUINEA PACIFIC OCEAN

.sV! '■5 Tf AUSTRALIA

0.5

C? WORLD ISOHYETAL MAP

120 100 140 160 120 100

ISOHYETS REPRESENTS INCHES OF MAXIMUM RAINFALL IN ONE HOUR FOR STORM OF 2-YEAR FREQUENCY

Figure 9-5. World isohyetal map.

Table 9-3. Surface Runoff Factors

Types of surface Factor

A*)halt pavements 0.80 to 0.95

Concrete pavements 0.70 to 0.90

Gravel or macadam pavements 0.35 to 0.70

Impervious soils* 0.40 to 0.65

Impervious soils, with turf* 0.30 to 0.55

Slightly pervious soils* 0.15 to 0.40

Pervious soils* 0.01 to 0.10

Wooded areas depending on surface slope and soil cover 0.01 to 0.20

•For slopes from 1 to 2 percent. Note. The figures given are lor comparatively level ground. For slopes greater

than 1 in 50 (2%) the factor should be increased by 0.2 for every 2 percent of slopes up to a maximum 1.0.

g. Compute the length of one pipe (in place). NOTE. Round up to an even whole number, then add 2' if there is no

headwall downstream. h Compute the total length of pipe in place, (length of one pipe, in

place times the number of pipes required). /. Compute the order length (total length required, in place, times 1.15).

Table 9—4. Recommended Gages For Nestable Corrugated Metal Pipe (CMP)

Pay Pipe required for.

Diem in

Inchei

Cron* sectional area (tq ft)

Fills op to 8 ft.

Fills up 20-ft fill

25 ft fill

30-ft. fill

35 ft. fill

40-ft. ftll

.35

55

79

1 23

1 77

2 41

3.14

4.91

7.07

9.62

12 57

15.90

19.64

23 76

28.27

33.18

38.49

16

16

16

16

16

16

16

14

14

14

12

12

12

10

10

16

16

16

16

16

16

16

14

14

14

12

12

10

10

10

16

16

16

16

16

16

16

14

14

12

12

10

16

16

16

16

16

16

16

14

12

12

16

16

16

16

16

16

14

14

12

10

16

16

16

16

16

16

14

12

12

10

16

16

16

16

16

16

14

12

10

8

8

MUST BE DESIGNED FOR

THESE FILL HEIGHTS AND

OTHERS ABOVE 40 FT. I

NOTES: CULVERTS MUST BE STRONG ENOUGH TO CARRY WEIGHT OF FILL ABOVE PLUS WEIGHT OF THE LIVE LOAD PASSING OVER ROAD.

CULVERTS BELOW LINE SHOULD BE STRUTTED DURING INSTALLATION.

243

244

Step 7. Ditch Design a. Guidelines.

(1) IfQ > 60 cfs, use a trapezoidal ditch. (2) If Q <. 60 cfs, use a triangular (vee) ditch. (3) Slope should be 0.5% to 2.0% without erosion controls. (4) Side slope should be 3:1, 1:1 when cut by grader. (5) Freeboard should be a minimum of 0.5 feet.

b. Trapezoidal. Compute as a rectangle, ignoring side slopes. See figure 9—6. Select width and calculate depth of water (d).

(1 ) A = dw d=A w

(2) w = 10 feet when cut by scraper d = A 10

(3) Cutting Depth = d + 0.5' c. Triangular. Select side slopes and calculate depth of water (d). See

figure 9-6.

(1) A = 1/4(BH) B = Xd + Yd H = d

d = • V

(2) If side slopes 3:1, 1:1

YK (3) Cutting depth = d + 0.5'

I=OA lx + y

AREA OF WATER d = DEPTH OF d

WATER 'A'

Yd Xd

W = WIDTH OF BOTTOM

DEPTH d OF

WATER

Figure 9—6. Ditch design.

(b) /il hasty computation method. (Use for an area that has a stream flowing through it). Step 1. Calculating the Design Area See figure 9- 7.

a. Locate the high water mark. b Measure the width of the stream at the high water mark (W^. c Measure the width of the stream at the bottom (V^)-

d Measure from the bottom of the stream to the high water mark (H). e. Calculate the design area (2 x cross- sectional area).

or: (2) (W1+W2)H

W| = WIDTH OF CHANNEL AT HIGH WATER AI ARK

WIDTH OF CHANNEL AT ROTTOM

H = VERITICAL DISTANCE FIOAI BOTTOM TO HIGH WATEI

2

SIZE OF CULVERT = AREA OF W AT El W A T* SA FETT FACTOR IOOX

Figure 9- 7. Computation of culvert size by hasty method.

245

246

Step 2. Culvert £>ofg/i a Find the critical (minimum) fill depth (Fm¡n).

b Compute the maximum pipe diameter (Dmax = 2/3Fmjn).

c Select the maximum pipe diameter that can be used from table 9—4. d Compute the most economical pipe size and number of pipes:

e Compute the length of one pipe (in place). NOTE Round up to an even whole number, then add 2' if there is no

headwall downstream. / Compute the total length of pipe in place (length of one pipe, in place

times the number of pipes required). g Compute the order length (total length required, in place, times 1.15).

(3) Culvert alinement Culverts are placed in natural drainage channels unless such installation would require an unusually long culvert or produce a sharp bend in the channel on the upstream side. Where old drainage channels are not encountered, culverts should be installed at right angles to the road centerline. Ditch relief culverts should be installed at an angle of 60° to the ditch centerline.

(4) Design criteria-CMP culvert. See figure 9—8.

Design area End area of one pipe from table 9—4

MIADWALl

• ITC

Figure 9—8. Culvert extended beyond fill to prevent erosion

lb) Select the culvert size based on the following: / Area of culvert required. 2 Minimum cover of ViD or 12 inches under the road surface,

(table 9- 4). 3 Culvert available.

(c) Place the inlet elevation at or below the ditch bottom. (d) Extend the culvert 2 feet minimum downstream beyond the fill

slopes. (e) Use bedding of 1/10D minimum. (f) Space multiple culverts a minimum of %D apart. (g) Desirable slope is 2 to 4%, minimum slope, 0.5%. (h) Always use a headwall upstream. (i) Rip—rap downstream to control erosion.

(5) Corrugated metal pipe—size and strength. See table 9—4. (6) Expedient culvert (fig. 9—9).

9-6. SOIL STABILIZERS

See table 9—5.

9-7. EXPEDIENT SURFACES

a. When normal means of construction are not available or time is limited, expedients must be used.

b. Expedient surfaces over mud must be structurally strong and spread the load over a wide area of the subgrade.

247

248

Si TROUGH sätiiV

4" LOGS

DRIFTPIN OR, SPIKE ALL LOGS

TOGETHER

a. LOG CULVERT

STAKES AND SPREADERS SPACED 8' C TO C

WRAP POSTS TOGETHER

WITH WIRE ROPE

8" x 10" LOGS

V

b. SANDBAG CULVERT

6* CENTER-TO-CENTER

rxiZTiA-er COLLAR

/ S'"'-:

I9H*

3“X12“ RANDOM LENGTHS'

rxarMf-cr CAP AND SILL

c. TIMBER CULVERT 3-XI2XI-6- COLLAR

Figure 9—9. Example of expedient culvert.

Table 9—5. Summary of Soil Stabilizers

MATERIAL FORM OF

MATERIAL APPLICABLE SOIL RANGE

ESTIMATED RANGE OF QUANTITY REQUIREMENTS

(%) +

MINIMUM CURING TIME

REQUIREMENTS

PORTLAND CEMENT GRAVELS SANDS SILTS, CLAYEY SILTS CLAYS

3— 5

4— *

LIME 1. HYDRATED CLAYEY

GRAVELS SILTY CLAYS CLAYS

2— 4 5—10 3— 8

2. QUICKLINE CLAYEY GRAVELS SILTY CLAYS CLAYS

2— 3 3— 8

BITUMINOUS MATERIAL:

1. ASPHALTIC CUTBACKS A. RC-70 TO RC-800

B. MC-70 TO MC-800

2. ASPHALTIC EMULSIONS

SANDS SILTY SANDS CLAYEY SANDS

SANDS SILTY SANDS CLAYEY SANDS SANDS SILTY SANDS CLAYEY SANDS

5— 7+ + 6— 10 6—10

5— 7 6— 10 6—10 5— 7 6— 10 6—10

1—3 DAYS

1—3 DAYS

•(■BASED ON DRY DENSITY OF EXISTING SOIL. ++ALL QUANTITIES LISTED FOR ASPHALTS ARE ACTUAL

BITUMEN REQUIREMENTS,EXCLUSIVE OF VOLATILES.

249

250

(1) Chespaling. Chespaling—mat roads (fig. 9-10) are composed of a series of mats 6% by 12 feet, or larger. The mats are made by placing small saplings 6'/: feet long and about VA inches in diameter side by side, and wiring them together with chicken wire mesh or strands of heavy smooth wire. A chespaling road is constructed by laying mats lengthwise with a 1—foot side overlap at the junction of the mats. The resulting surface is 12 feet wide. Unless laid on wet ground, this type of road requires periodic wetting down to retain its springiness and to prevent splitting. It also requires extensive maintenance.

FINISHED MAT SIZE 6 1/2' BY 12' OR LARGER

Figure 9-10. Chespaling.

(2) Corduroy (a) Standard corduroy (fig. 9-1 la).

Six—to—eight—inch diameter logs about 13 feet long are placed adjacent to each other (butt to tip). Along the edges of the roadway thus formed, place 6 inch diameter logs as curbs (drift—pinned in place). Pickets about 4 feet long are driven into the ground at regular intervals along the outside edge of the road to hold the road in place. To give this surface greater smoothness, full up the chinks between logs with brush, rubble, twigs, etc.; then cover the whole surface with a layer of gravel or dirt. Side ditches and culverts are constructed as for normal roads.

(b) Corduroy with stringers (fig 9-11b). The corduroy decking is securely pinned to stringers and then the surface is prepared as (a) above.

(c) Heavy corduroy (fig. 9-llc). Heavy corduroy involves the use of sleepers, heavy logs 10 to 12 inches in diameter and long enough to carry the entire road, placed at right angles to the centerline on 4 foot centers.

(3) Tread roads (fig. 9-12). Tread roads are made by preparing two narrow parallel treadways of select material for vehicular wheels to use over otherwise impassable ground. The material used may be anything from palm leaves to 4 inch planks with a consequent wide variation in the capacity and durability of the road. The most important single type of tread road is the plank tread road. Sleepers 12 to 16 feet long are first laid perpendicular to the centerline, on 3 to 4 foot centers, depending on the loads to be carried and subgrade conditions. If finished timber is not available, use logs as sleepers. Then place 4— by 10—inch planks parallel to the line of traffic to form two treads about 36 inches apart. Stagger the joints to prevent the forming of weak spots. Next install 6— by 6- inch timber curbs on the inside of the treads.

251

252

GUARDRAIL

PICKET

13-0

6" TO 8" LOGS

CROSS SECTION

A. STANDARD CORDUROY

13-0

6" TO 8" LOGS

PICKET

8" LOG STRINGERS

CROSS SECTION

B. CORDUROY WITH STRINGERS

t 13’ - 0"

6" TO 8" CROSS LOGS & STRINGERS

A m% -8" TO 10” SLEEPERS ON 4" CENTERS

LENGTH DEPENDS ON GROUND CONDITION

CROSS SECTION

C. HEAVY CORDUROY

Figure 9-11. Corduroy road surfaces.

w

PLAN

SLEEPERS

4” X IO"

f/t

X 7

1

STAGGER JOINTS

FLOORING 3" X 10" X lO'-O

F-IM'ffl

CURBS 6” X 6” X lO'-O*

p ^

CROSS SECTION

Figure 9—12. Tread road.

253

254

c. Expedient surfaces over sand must confine the sand in a manner which will develop the necessary load—carrying capacity.

(1) Wire mesh. Chicken wire, expanded metal lath, and chain link wire mesh (cyclone fence) may be used as road expedients in sand. They should not be used on muddy roads since they prevent grading and reshaping of the surface when ruts appear. The addition of a layer of burlap or similar material underneath helps to confine the sand. Any type of wire mesh expedient must be taut. To accomplish this, the edges of the wire mesh road must be picketed at 3-to—4 foot intervals. Diagonal wires, crossing the centerline at 45° angles and attached securely to buried pickets, fortify the lighter meshes. As with all other road surfaces, the more layers used the more durable the road will be.

(2) Army track (fig. 9-13). A portable timber expedient known as Army track can be used to pass vehicles across sandy terrain. The track consists of 4 x 4 or larger timbers threaded at each end on a VS—inch wire rope and resembles the ties of a railroad track with a cable running through the ties on each side. The timbers must be spaced not greater than the distance which will allow the smallest wheeled vehicle using the road to obtain traction. Cable holes are drilled at a 45° angle to the centerline so the cable will bend and prevent individual timbers from moving together. Cables are anchored securely at both ends. The spaces between the timbers are filled in with select material to smooth out the surface.

Figure 9—13. Army track.

</ Mí’lul laiuhiií; Mais (Jig. 9-1J). Airfield landing mats can be used to form an expedient road surface over either mud or sand. Generally, only M8 and M8A1 would be used in this capacity and, as far as road construction is concerned, their characteristics are the same. When used on sand, the metal landing mats can be placed directly on the sand to the length and width desired, though burlap on straw underneath the planking is desirable. The smoother and firmer the subgrade, the better the resulting road. The mat is placed so that its long axis is perpendicular to the flow of traffic and each section overlaps the previous one enough that the manner of connecting prescribed for the particular mat can be accomplished.

If a width greater than the effective length of one plank is constructed, half—sections are used to facilitate staggering of joints. M8 mat can be used on mud but, being perforated, the mat sinks until it becomes ineffective. Experiments have proven that with the use of an underlying layer of brush on burlap to prevent the pumping of the mud, a fairly effective expedient can be constructed. A second layer of the steel mat, laid as a treadway over the initial layer, will further increase its effectiveness. In either case, the foundation should be as smooth as possible.

Figure 9-14 Metal landing mat road.

255

CHAPTER 10

ARMY AIRFIELDS. HELIPADS, AND HELIPORTS

10-1. GENERAL

Information listed for airfields is for reference only. For design specifications refer to TM 5- -330.

10-2. ARMY AIRCRAFT AND HELICOPTER CHARACTERISTICS

Aircraft and helicopter characteristics are shown in tables 10—1 and 10--2.

10-3. HELIPADS IN HEAVILY FORESTED AREAS

a. Personnel. The suggested work crew consists of an officer in charge and two teams, each composed of a noncommissioned officer and five enlisted men ■ - two chain saw operators, two axemen men, and one brush hook man. Weight of an individual is assumed to be 200 pounds.

b. Equipment. The following equipment per team is to be contained in the equipment box. The weight of the box loaded with the equipment is approximately 333 pounds.

2 Chain saws 1 Brush hook 3 Axes 1 Block and tackle set (1 single and 1 double) 1 Set climbers with safety straps 1 Can gasoline

16 2'/:, lb. Blocks of C-4 2 Cans of oil

250 Meters of Demo wire 1 Galvanometer 1 Ten-cap blasting machine

20 Electric blasting caps 1 Brace with bits 1 Sledge hammer 2 Wedges 2 Screwdrivers 2 Pliers

c. Procedure. (1) Equipment and personnel delivery. Equipment is delivered into

the proposed landing area by lowering it in a box. Modification of the equipment requirements may be desired depending upon the expected area of employment. The box is slung beneath the helicopter by the aircraft cargo hook. Rappelling ropes are then attached to the box and secured to the floor—mounted Darings inside the helicopter. Since, in the event of an in-flight emergency, the pilot cannot jettison the external load, engineers within the cargo compartment are responsible for cutting or releasing the ropes upon direction by the pilot or copilot. To lower the box to the ground, the cargo hook is released and the box is lowered by hand using the attached rappelling ropes. All personnel in the team are equipped with field equipment, machetes, weapons, and other items which are carried on the person during rappelling activities. Other field gear, if utilized, is inclosed in the equipment box lowered from the helicopter.

(2) Preparation of landing zone. (a) The first man on the ground removes the rappelling ropes from

the equipment box. The officer in charge starts laying out strips of engineer tape to mark the perimeter of the proposed landing area.

(b) The chain saw crews, axe crews, and brush hook man move into the proposed landing area, felling and clearing all vegetation within the perimeter of the tape—marked landing area.

(c) Upon felling the trees as close as possible to ground level, necessary limbing and bucking is done for easier removal. It is imperative that in felling and cutting, any vegetation that may be sucked up into the helicopter blades must be removed from the landing area proper. Vegetation should not be burned. Time permitting, or under marshy conditions, the timbers felled may be used to prepare a hardened landing pad. Landing pad logs are leveled to insure a satisfactory surface upon which the helicopter skids can rest without danger of skid damage. The perimeter of the landing area must be checked to assure vertical clearance. In densely wooded areas

258

Table 10—1. Aircraft Characteristics Used in Design of Theater of Operations Airfields

Airfield typ«

Anticipated ■ervica life

Ponible using aircraft

U.S. type Grots weight

Ground run at sea laval and 59«.

Minimum length

required, ft Width

ft

Battle area Light lift Medium lift

Forward area: Liaison

Surveillance

Light lift

Medium lift

Support area.

Liaison Surveillance

Light lift Medium lift

Heavy lift

Tactical

Rear area:

Army

Medium lift

Heavy lift

3 days C 7 A8

C-1308

C -123

O I-

OV-1a

C- 7Aa

C- 130a

C-7A

0-1a

OV- Ia

C 7Aa

C 130“ C- 7 A C 124-

C- 141a

F--4C*

F —101

OV- Ia

C-7A

0-1

C-1308

C-1418

C--13S8

C- 133

F-4C* F 106® F-100

F--101

F 104

25.000

100.000

48.000

2.400

15.800

28.500

110,000

28.500

2.400 15.800

28.500 130.000

28.500

190.000

260.000

56.000

51.000

15.800 28.500

2.400

155.000

316.000

250.000

300.000

56.000

53.000 37.800

51.000

28.000

625

1,600

1,600

390

2,000

625

2,000

625

390

2,000 625

2,800 625

4.000 2.400

4.000

4.000

2.000

625

390

4.000

3,900

6,700

5.300

4.000 5.300 5.000

4.000

5,200

1,000

2,000

750

2.500

1,200

2.500

1,000 3.000 1.500 3.500

6.000

3,000

6,000

10,000

50

60

60

60

60 60

SO 60 60

60

72

156

aParticular aircraft that is critical in load and/or ground run from which area requirements, geometries, and expedient surfacing requirements were developed.

round run lengths indicated are for classification and can undergo changes depending on operating weight of aircraft, pressure altitude correction, temperature correction and local conditions.

Table JO-2. Helicopter Characteristics

Hdkopfr Dtignatiow

Dwgn Name

Overall Oimentiom Ft

Length Width

Weight. Kip»

Maximum takeoff Gear Type

OH-6A*

OH-13S OH-23G

OH—68A

UH- 16

UH-1C

UH—ID*

CH- 34

CH—370

CH- 47A

CH—470

CH-47C CH-54A*

AH- 1G

CayuM

Sioux

Raven

Kiowa

Iroquois

Iroquois

Iroquois

Choctaw

Mojave

Chinook

Chinook

Chinook

Flying Crane

Huey Cobra

30.30

43.25

43 25

41.00

52 83

52.83 57.01

65.83

08.00

98.01

09.00

99.00

88.41

52.97

26.30

37 00

35 16

35.30

44.00

44.00

48.00

56.00

72.00

56 16

60 00

60.00

72.00

44.00

8.20

1200

10 16

960

1641

12.67

17.16

15.83 22.00

18.50

18.67

18.67

25.33

11.00

1.16

1 91

1.91

1.59

5.06

4.82

4.92

7.76

21.50

16.04

19.59 20.48

19.82

2.70

2.85

2.80

3.00

9.50

9.50

9.50

13.30

31.00

33.00

40.00

46.00

42.00

Skid

Skid

Skid

Skid

Skid

Skid

Skid

Single-conventional

Twin-conventional

Twin-quad

Twin-quad

Twin-quad

Single-tricycle

Skid

and jungle forest, it will be necessary to fell additional trees to provide an approach and departure zone. The normal time for clearing such a landing

zone in tropical zone forests by well—trained troops should not exceed 3

hours for a UH—1 and smaller helicopter landing zones.

10-4. LAYOUT AND NOMENCLATURE

Landing reference panels serve as a visual guidance system during

approaches. They must be positioned and firmly secured adjacent to the

touchdown point before the landing of a helicopter. Figure 10—1 shows

correct placement of landing reference panels on the ground. The general

layout and nomenclature of Army helipads and heliports is illustrated in

figures 10-1 thru 10-3.

259

260

WIND DIRECTION

©

LANDING AREA

PANELS

®T PAD

©

I-

¥

LANDING DIRECTION

PANELS ARE LAID OUT ON THE RIGHT SIDE OF THE LANDING PAD.

FOR DIMENSIONS OF THE LANDING AREA CORRELATE

ITEM NUMBERS TO TABLE 10-3

Figure 10—1. Panel layout of landing zones.

LANDING PAD/ASE A

; © l°l ÎQ@i © 0

Si ©

© PLAN

El ISO MULTIPLE AREA DIMENSIONS FOR LANDING ZONES.* SEE TABLE 10 4

(VASIAT^T^ (VASIABie)

*1 I'* envi50'

(¡2) H ^ H K ^ w Ci) ©

-H (U) IANOINO AREA El =0

FOR GEOMETRIC REQUIREMENTS CORRELATE ITEM NUMBERS TO TABLE 10-SAND TABLE 10 4

SECTION

ISOMETRIC VIEW

Figure 10—2. Geometric layout of landing zones

262

ROI SYSTEM

O □ □□□ [0 © I © Mb

©

SEE DETAIL A

PLAN

FOR MINIMUM GEOMETRIC REQUIREMENTS CORRELATE ITEM NUMBERS TO TABLE 10-3 AND TABLE 10-4.

©

□ n □□ L i

T © ©-

DETAIL A ©

□ g

il QM

AMMO POINTS

Figure ¡0-3. Geometrie layout of forward area rejueling and rearming heliports

10- 5. DESIGN FOR LANDING ZONES

The general design requirements for landing zones and multiple area landing zones are shown Tables 10—3 and 10—4.

10 6. DUST CONTROL/SOIL WATERPROOFING

Sprinkling with water, lime solutions, and oils provide temporary relief from dust. Longer relief is achieved by use of asphaltic materials, such as Peneprime (APSB), or special compounds such as DCA-70. Any asphaltic material must be allowed to cure before being exposed to traffic. Asphaltic cutback materials also serve to waterproof soils. See table 10- 5 for approximate area to be sprayed.

10 -7. MARKING IMPROVED HELIPADS AND HELIPORTS

The touchdown area marker for helipads is shown in figure 10—4. The dimensions of the pattern relative to the pad size are shown in this figure. The center of the marking pattern will always be placed at the center of the pad. This marking pattern will also be placed at both ends of all runways and taxi—hoverlanes used for landings. This pattern is intended as an indication of a safe touchdown point and is not to be placed at locations, such as parking areas, at which helicopters normally do not land or take off. The marking pattern will be white, but should be edged in black when placed on a light-colored surface. The broken line border around the perimeter of the pad will also be included on all helipads.

10- 8. LANDING MATS

The types of landing mats and membrane are classified as follows: a. Light duty landing mat- M6, M8, M8A1, and M9. b. Medium duty landing mat— MX18B, MX19, and AM2. c. Membrane—T17.

263

264

Table 10—3. Minimum Geometric Requirements for Landing Zones.

Description

FORWARD AREA

OH 6A OH-56 AH-1G UH-1H CH-47 CH-64

LANDING PAD AND LANDING AREA

Length, ft

Width, ft

Landing area length, ft

Landing area width, ft

Parking pad grade in any

direction, % Maximum

Lateral clearance from rear and

sides of parking pad to fixed

and/or movable obstacles except

other aircraft, ft

C-C spacing of parking pads, ft

Spacing from edge of Taxt-

Hoverlane to edge of parking

pad, ft

20

20 too too

too too

so 25

150

125

65

150

50

50

150

150

65

150

TAXI HOVERLANE

Width, ft1

Longitudinal grade of Taxi

Hoverlane. % Maximum

Transverse grade of Taxi-Hoverlane

% Maximum

140

10

5

180

10

5

200

10

5

HELIPORT APPROACH AND DEPARTURE ZONE

Approach-departure surface ratio

Length, ft

Widths, ft

a At end of clear ¿one or

Taxi-Hoverlane

b At outer end

10 1

1500

75

850

10 1

1500

10 1

1500

140

650

10 1

1500

140

850

10:1

1500

180

850

10:1

1500

200 850

HELIPORT TAKEOFF SAFETY ZONE

Length, ft

Width, ft SAME AS APPROACH DEPARTURE ZONE

SERVICE ROADS

115 115 115 11.5

Taxi Hoverlane is used for take off and landing

Roads should be located so as to require the least effort

Tuble 10-4 Minimum Geometric Requirements for Multiple Area Landing Zones.

Item No. Description

One-ship landing zone Length Width

Two-ship trail landing zone Length Width

Two-ship side-by-side landing zone Length Width

Three-ship trail landing zone Length Width

Four-ship side-by-side trail Length Width

Forward area

UH-1 CH--47

100 100

180 100

100 170

260 100

180 170

150 125

250 125

150 220

375 125

250 220

Table 10—5. Dust Control Requirements for Heliports

Dimension of area requiring dust control (ft)

OH-6A Cayuse

UH -ID Iroquois

AH-1G Huey Cobra

CH-47A Chinook

CH-54A Sky crane

Taxi-hover Lane and Parking Pads

Takeoff and Landing Areas

150

NOTH Measurements are taken from the center of rotation of the controlling aircraft and are approximately equal to the radius of the area affected by the rotor downwash.

265

266

r C-Jff r

A/2

T A/2

4-

[S S MIN

MAX

10'

5’

PAD SIZE ?i-UL

PATTERN SIZE (A) IS 0.80 HELIPAD SIZE

DIMENSIONAL CRITERIA HELIPAD SIZES PATTERN LINE

WIDTH (B) BORDER EDGE

WIDTH (C)

FEET

12 19

20-40

41 60

61-60

81-99

1.0

2.0

3.0

4.0

6.0

0.5

1 0

1.5

2.0

2.0

Figure 10—4. Touchdown area marker.

10-9. REPAIR OF ARMY AIRFIELDS

a T-l 7 Membrane. When a tear occurs in the membrane surfacing on which antiskid compounds have been applied, the failed area should be repaired by slitting it in the form of an X and folding the four flaps back. Adequate membrane surfacing should then be removed from a roll of membrane and placed beneath the antiskid coated membrane so that it extends beyond the failed area of surfacing for approximately 2 ft on all sides. Adhesive should then be applied to the top of the membrane removed from the membrane roll and to the bottom of the surfacing coated with antiskid compound. Adhesive can be spread over the membrane with long handled paint rollers. After the adhesive becomes tacky (2 to 5 minutes), the flaps that were folded back previously should be placed in their original positions, and the adhesive should be allowed to set for approximately 15 minutes. The patched area should then be rolled with a jeep. This manner of patching should also be used for areas of surfacing that are not coated with antiskid compound, but surface patches can be used on uncoated membrane, particularly when the opening being patched is small.

b M8A1 and M8 Mats. (1) Removal.

(a) Unlock the end connector bars (hooks) at both ends of the panel to be removed.

(b) Remove the 12 (6 per side) side connector locking lugs that hold the panel. (Break the weld on the locking lugs of the M8.)

(c) Drive the panel laterally (approximately 1 inch) until the side connector hooks are centered in the side connector slots.

(d) Pry the side connector hooks out of the slots. (e) Drive the panel laterally to clear the end from the overlapping

end of the adjacent panel. (f) Remove the panel from the runway.

(2) - Replacement. (a) Remove the side connector locking lugs of a new panel (break

the welds on the MB) to allow the panel to slide laterally when positioned properly. Orient the new panel in all respects so that it will be in the approximate position in the run of that of the damaged panel.

267

268

(b) Drive the end of the new panel under the end of the adjacent panel so that the adjacent panel will overlap the new panel. (The panel will then be in its approximate final position.)

(c) Adjust the panel to aline the side connector hooks with the side connector slots. Engage the two by hammering together.

(d) Drive the panel laterally (in the same direction in which panels in the same run were slid during initial placement) to hook the side connectors.

(e) . Lock the end connectors bars (hooks on the M8) at both ends of the panel.

(f) Replace and engage the side connector locking lugs in the locking lug slots (reweld on the M8).

c. AM2 Mat and XM18B. ( 1 ) Sliding method.

(a) With a tooth of the harrow on a motor patrol or with other power equipment, engage a panel end in the same run with the damaged panel and force the entire run to slide out until the damaged panel clears the runway or taxiway edge.

(b) Disconnect the ends of all panels that have been slid from the runway by removing the end connector bars.

(c) Discard the damaged panel. Connect a new panel it its place and lock at the end with the adjacent panel in the run. With a tooth of the motor patrol harrow, engage the panel end and slide the panel until only 2 to 4 in. of the new panel protrude past the edge of the runway.

(d) Reinstall succeeding panels as In step (c) until all panels in the run are in their original position.

(2) Cutting method. (a) Cut the damaged panel in seven places, as shown in figure

10-5.

(b) With a pry bar, force up cut No. 4 and hinge out one side of the cut panel.

(c) Force up and hinge out the opposite side. (d) Force out the end connector bars, and remove the two

triangular parts by forcing down or up and out. (The adjacent panels can be pried up so that the triangular parts can be removed more easily.)

(e) Use a special panel and accessories to replace the damaged panel.

ORDER OF CUTS Æ OVERLAP

f-® MALE

^CUTNO©

CUT TO HIT LOCK BAR VOID, DEPTH OF SAW CUT = 1 INCH.

CUTS (2) THRU (6) CUT COMPLETELY THROUGH PANEL. DEPTH OF SAW CUT = 1.6 INCHES

A

UNDERLAP

CUT NOJ® CUT IN GROOVE BETWEEN PANELS WITH SAW SET AT 10 DEGREE BEVEL TO HIT VOID AT LOCK BAR, DEPTH OF SAW CUT = 12 INCHES

-FEMALE

-©

Figure 10—5. Cutting method for removing AM2 or XM18 landing mats.

(f) Place the accessories in the void and connect and aline in such a way that the panel will fit on top of (overlap) two edges and hinge on a third edge.

(g) Engage the hinge on the panel and drop into position. (The normal underlapping end of the panel contains an end connector bar, recessed to prevent interference when dropped into position and secured with two setscrews.) Remove the screws and use a pointed rod to work the end connector bar into the slot of the adjacent panel. Replace the setscrews and screw down along the side edge of the end connector bar to prevent the bar from disengaging.

(h) Place the top rail for the side and secure with countersunk alien screws.

269

270

d XM19 Mat. (1) Cutting method.

(a) Cut the damaged panel in four places as shown in fig. 10-6.

(b) With a pry bar, force up one of the triangular cuts. (c) Pry up the remaining three pieces.

(2) Replacement. (a) Place the replacement panel in the void and engage the hinges. (b) Place the connector bar in the slot and secure the countersunk

alien screws. e. Subgrade Failure. Subgrade failure normally requires removal of

material and replacement with a better quality material. When subgrade failure occurs in an area that is not readily accessible by disassembly of matting, then procedures stated in paragraph 10- 9 a thru d can be utilized to gain access to the area to be repaired.

Figure 10—6 Damaged panel of XM19 landing mat cut for removal from mat field.

10-10. USERS OF FM 5-34

Users of this manual should always check construction criteria with local command standards, particularly in situations involving aircraft with which the Army has little or no experience.

CHAPTER 11

RIGGING

11-1. FIBER AND WIRE ROPES

a. Data. See tables 11—1 and 11-2 for data on manila, sisal, and wire rope.

b. Safety Factors. The safety factors normally used with wire rope are given in table 11 —3. Where age and condition of rope are doubtful, or where human life or expensive equipment may be endangered by rope failure, apply a safety factor of at least 8.

c. Safe Working Capacity. The following general formula can be used to compute safe working capacities.

Fiber Rope: T = 4D 2

Wire Rope: T =

Safety Factor

32D2

Safety Factor Where:

T = Safe working capacity in tons D= Nominal rope diameter in inches

11-2. MECHANICAL ADVANTAGES OF VARIOUS BLOCK ARRANGE- MENTS

a. Block and Tackle. Figure 11 — 1 shows examples of typical tackle systems. A simple tackle system advantage is figured by counting the number of I ines leaving the load (fig. 11 — 1).

(1) ©-Mechanical advantage of 2 (2) (2) — Mechanical advantage of 3 (3) @ - Vechanical advantage of 5 (4) In a compound system with 5 lines leaving the load (®, fig.

11 — 1), and the fall line of this tackle attached to a traveling block with 2 lines supporting it, the mechanical advantage is 2 times 5, or 10.

271

272

Table 1J — I. Properties of Manila and Sisal Rope

Nominal diameter.

Circum- ference,

Lbs. per ft.

No. 1 manila

Breaking strength,

tons

Safe working capacity

tons (F.S. = 4)

Sisal

Breaking strength,

tons

Safe load, tons

(F.S. = 4)

%

%

%

V.

%

’/. 1

1%

IV.

1V4

1%

2

TA

3

%

i%

2

2%

2%

3

3'/j

3%

4'A

S'A

6

7yA

9

0.20

.040

.075

.133

.167

.186

.270

.360

.418

.600

.895

1.08

1.35

2.42

0.30

0.67

1.32

2.20

2.70

3.85

4.50

6.00

6.75

9.25

13.25

15.50

23.25

32.00

0.07

0.16

0.33

0.60

0.67

0.96

1.12

1.50

1.69

2.31

3.31

3.87

5.81

8.00

0.24

0.54

1.06

1.76

2.16

3.08

3.60

4.80

5.40

7.40

10.60

12.40

i860

25.60

0.06

0.13

0.26

0.44

0.54

0.77

0.90

1.20

1.35

1.85

2.65

3.10

4.65

6.40

NOTES.

1. Breaking strength and safe toads given are for new rope used under favorable conditions. As rope ages or deteriorates, progressively reduce safe loads to one-half of values given.

2. Cordage rope is issued by circumference sizes.

Table 11-2 Breaking Strength of 6 x 19 Standard Wire Rope

Diameter <n 2

Approximate weight Ib/ft

Breaking strength, tons of 2000 lbs

T raction steel

Plow steel

Improved plow steel

Extra improved plow steel

%

V, %

%

K

7s

1

IV.

1%

1%

1%

2

0.10

0.23

0.40

0.63

0.90

1.23

1.60

2.03

2.50

3.60

1.4

2.1

3.6

5.5

7.9

10.6

13.7

17.2

21.0

29.7

2.6

4.0

6.8

10.4

14.8

20.2

26.0

32.7

40.6

56.6

2.39

5.31

9.35

14.5

20.7

28.0

36.4

45.7

56.2

80.0

108.0

139.0

2.74

6.10

10.7

16.7

23.8

32.2

41.8

52.6

64.6

92.0

124.0

160.0

7.55

13.3

20.6

29.4

39.8

51.7

65.0*

79.9

114.0

153.0

198.0

^6 x 19 means rope composed of 6 strands of 19 wires each. ^Breaking Strength of 6 x 7 or 6 x 37 wire rope is 94% of the breaking strength of

a 6 x 19 rope of an equal diameter and identical material. Example: Find breaking strength oí V/* inch, 6x7, Improved Plow Steel wire rope Breaking strength of 6 x 19, VA inch, Improved Plow Steel wire rope B 64.6 tons Breaking strength (6 x 7) B .94 x 64.6 s 60.7 tons

273

274

Table 11—3. Wire Rope Sajety Factors

Type of service Minimum safety factor

Track cables

Guys

Miscellaneous hoisting equipment

Haulage ropes

Derricks

Small electric and air hoists

Slings

3.2

3.5

5.0

6.0

6.0

7.0

8.0

*Where age and condition of rope are doubtful, or where human life or expensive equipment may be endangered by rope failures, apply a safety factor of at least 8.

(5) A more complicated compound system ( (jj), fig. 11 — 1) is made up of two simple systems, each of which has 4 lines supporting the load. The traveling block of the first simple system is fastened to the fall line of the second simple system, and the mechanical advantage of this compound system is 4 times 4, or 16.

b Chain Hoists. With a chain hoist, a load can remain stationary without requiring attention, and the hoist can be operated by one man to raise loads of several tons.

í? fí

W =2P

W“3P

(D

Figure 11 — 1. Mechanical advantage of various tackle riggings

c Determining A dual Pull.

FL = friction loss, the amount of force lost to friction in the system. AP = actual pull, the amount of force required on the fall line to lift the

load. Ff = friction factor, varies with conditions of the blocks.

1/10, excellent condition (new) 1/8, good condition 1/5, fair condition

Ns = number of sheaves, total number of sheaves in the system including change-of- direction blocks.

MA = theoretical mechanical advantage W|_ = weight of the load

275

276

Example: Assume WL = 2500 lbs

Ns = 6

MA = 6:1 Ff = 1/5

Then FL = WLx Nsx Ff

= 2500 lbs (6) (1/5) = 3000 lbs

And

AP-WL + FL

MA

= 2500 + 3000

6 = 916.67 lbs

11 3. PICKET HOLDFAST

a. Holding Power. Sound pickets, 5 feet long, 3 in. in diameter, driven 3 feet into the earth, spaced 3 to 6 feet apart, and inclined away from the load at an angle of 15°, should stand the pull indicated in table 11-4.

Table ¡1—4. Picket Holdfast Capacities

Typ« of hoklfait

Undis- turbed Wet clay

and gravel

Wet river

day and sand

Single picket

1-1 Picket holdfast

1- -1--1 Picket holdfast

2- 1 Picket holdfast

3- 2-1 Picket holdfast

700

1400

1800

2000

4000

630

1260

1620

1800

3600

350

700

900

1000

2000

b. Picket Hold)asi, 1 — 1 —I Combination (Jig. 11—2)

1800 LB

1-1-1 COMBINATION

Figure 11-2 Picket holdfast l — l-l combination

c Picket Holdjast. 3—2—1 Combination (Jig IJ—3)

4000 LB

3-2-1 COMBINATION

Figure 11—3. Picket holdjast. 3—2—1 combination.

11-4. DEADMAN (fig. 11-4)

Deadman may be constructed of logs, timbers, or steel beams. For complete design procedures refer to TM 5—210.

277

278

BACKFILL

GROUND —Al5°J**-

85

m

Figure 11-4 Log deadman.

115. ATTACHMENTS

a. Clips. Clips are used in making eyes in wire ropes. The correct method of attaching clips is shown in figure 11-5. The base of each clip should bear against the running end or long line, and the U—bolt against the standing end or short line. The number and spacing of clips and the proper torque to be applied are shown in table 11—5.

b. Wedge Socket (¡ig 11—6). The wedge socket is used when the fitting must be changed at frequent intervals. This socket has two parts, the socket proper with a tapered opening for the wire rope and a small wedge to go into this socket. The wire rope must be inserted in the wedge socket so that the running part of the rope will form a nearly direct line to the clevis of the fitting. If properly mounted, a wedge socket will tighten when a strain is put on the wire rope.

Table 11—5. Number. Size, Spacing, and Torque of Assembly (Prnhnhie Effirlency Factor =

Clips for Wire Rope 80%)

Wire rope diameter

(inch) (mm)

Nomine! size of clips

(inch)

Number of

clips

Spacing of

clips (inches) (mm)

Torque to be applied to nuts of clips

(ft—lb)(m-kg x 0.1382)

5/16

3/8

7/16

1/2

5/8

3/4

7/8

1

1 1 /4

1 3/8

1 1 ¡2

1 3/4

(7 95)

(9.52)

(11.11)

(12 70)

(15.85)

(19.05)

(22.22)

(25.40)^

(31.75)

(34.92)

(38.10)

(44.45)

3/8

3/8

1/2

112

5/8

3/4

1

1

1 1 M

1 1/2

1 1/2

1 3/4

(50)

(57)

(70)

(76)

(95)

(114)

(133)

(152)

(1901

(210)

9 (230)

10 1/2 (267)

2

2 1/4

2 3/4

3

3 3/4

4 112

5 1/4

6

7 1/2

8 1/4

25

25

40

40

65

100

165

165

250

375

375

560

(3 5)

(3 5)

(5 5)

(5 5)

(9 0)

(14)

(23)

(23)

(35)

(52)

(52)

(78)

NOTE: The spacing of clips should be six times the diameter of the wire rope. To assemble end-to-end connection the number of clips indicated above should be increased by two, and the proper torque indicated above should be used on all clips; U-bolts are reversed at the center of connection so that the U-bolts are on the dead (reduced load) end of each wire rope.

Figure 11—5. Wire rope clips

280

/

Figure 11—6. Wedge socket and fitting.

116. SLINGS

a. Single Slings. (1) A basket hitch is a single sling passed under the load with both

ends hooked over the hoisting hook (A, fig. 11-7).

(2) Single slings with two hooks are sometimes used for lifting stone and 55 gallons drums (B, fig. 11—7).

(3) The double anchor hitch is used sometimes for hoisting cylindrical objects (C, fig. 11—7).

b Endless slings. (1) The anchor, or choker, hitch is a common method of using an

endless sling by casting the sling under the load and inserting one loop through the other and over the hoisting hook (D, fig. 11—7).

(2) For a basket hitch, the endless sling is passed around the object and both remaining loops are slipped on the hook (E, fig. 11 —7).

(3) The toggle hitch is a modification of the basket hitch and is used only for special application (F, fig. 11- 7).

11- 7. SUNG LOAD FORMULA

a. Stress. The stress of tension in each leg of a sling depends on the number of legs, the angle of the sling leg, and the total load.

b. Formula.

W L — x —

where T = tension, in Ibs N = number of legs W = weight of load in Ibs V = vertical distance, in ft L = length of leg, in ft c. Example Problem. Is it safe to use a %—inch-diameter manila rope

sling to lift a 2,000—pound load with a 4—leg sling which has a vertical distance of 6 feet and length of leg of 12 feet (fig. 11—8)?

T = — x — =1,000 pounds. 4 6*

The tension on each leg will be 1,000 pounds. The safe working capacity of %—inch-diameter manila rope from table 11—1 is 0.67 tons or 1,340 Ibs. Since the safe working capacity is greater than the tension, the rope is safe to use.

11- 8. HELICOPTER SLING DESIGN

a Strength of Sling. (1) For a single leg sling, the minimum safe load capacity-should be

twice the weight of the load. (2) For a multiple leg sling, each leg should have a minimum safe load

capacity equal to the weight of the load.

b. Length of Sling Legs. The length of each sling leg should be the same as the greatest dimension of the load (L max).

N X V

2,000 12

281

282

A.

V V

w B

BASKET HITCH STONE-DOG HITCH DOUBLE ANCHOR HITCH

c. Stabilization of Loads. Helicopter sling loads are stabilized by one or more of the following methods:

(1) Reduce the air speed of the helicopter. (2) Increase the weight of the load. (3) Increase the surface area to the rear of the center of gravity of the

load by using a drone chute or by adding weight to the front 1/3 of the load.

D ENDLESS SLING ANCHOR HITCH

ENDLESS SLING TOGGLE HITCH

ENDLESS SLING BASKET HITCH

Figure 11-7. Hitches.

d Safety. ( 1 ) Padding should be placed on the sling where rubbing may occur. (2) To prevent in-flight "flapping" of prefabricated nylon slings,

twist each sling leg one turn for every 3 feet of length. (3) The distance between the top of the load and the bottom of the

helicopter should be a minimum of 9 feet.

A 12'

i 2000 LBS

Figure IJ-8. Sling Stresses.

11-9. GROUND CREW

a. Positioning. See figure 11—9.

b. Hand Signals. See figure 11—10.

283

284

í SIGNALMAN

DURING APPROACH

WIND

V

y DURING RELEASE AND HOOKUP

CARQi

HOOKUP MEN 20'

— to

30-

DURING APPROACH & HOOKUP

(AND RELEASE IF REQUIRED)

LANDING AREA

DURING TAKEOFF & RELEASE

EMERGENCY EMERGENCY

HELICOPTER MOVES LEFT ALL GROUND PERSONNEL MOVE RIGHT

•THIS DISTANCE MAY VARY. DEPENDENT UPON THE SPECIFIC ENVIRONMENT, E.G.. TERRAIN FEATURES'. WEATHER CONDITIONS. AND TYPE OF HELICOPTER EMPLOYED.

Figure 11--9 Position diagram for hook-up/release of helicopter sling loads

SIGNALS FOR DIRECTING HELICOPTERS

'HOVER MOVE UPWARDS MOVE MOVE TO RIGHT MOVE TO LEFT MOVE FORWARD DOWNWARDS

A?

WEIGHT OF CARGO

RELEASE SLING LOAD

TAKEOFF MOVEHOOK DOWN OR UP

CUT ENGINES MOVE REARWARD

HOOKUP COMPLETED

MARSHALING AFFIRMATIVE FINISHED SIGNAL

NEGATIVE SIGNAL

Figure J I-10. Hand signals

285

286

c. Safety. Police area thoroughly. (1) Ground personnel should wear:

(a) Steel helmets. (b) Protective masks, or dust goggles with respirator. (c) Earplugs.

(2) Helicopters acquire a large charge of static electricity during flight. A static discharge probe, which is not issued, is used to neutralize the charge. The probe consists of an insulated contact rod joined to a IB'—25' length of metallic tape or wire, which in turn is attached to a ground rod. The ground rod is driven into the earth and the contact rod is held by a ground crewman and touched to the helicopter hook, thus grounding out the stored electrical charge. The ground crewman should not grasp the hook to released the probe. Likewise, the sling should be attached without grasping the hook.

11-10. SAFE CAPACITY OF SPRUCE TIMBER AS AGIN POLE

See table 11—6 for these capacities. Approximate weight of timber is 40 pounds per cubic foot.

Table 11 — 6. Safe Capacity of Spruce Timbers as Gin Poles m Normal Operations

Size of timber. Safe capacity for given length of timber, lbs

20 ft (6 m)

25 ft (7.5 m)

30 ft (9 m)

40 ft (12m)

50 ft (15 m)

60 ft (18m)

6 dia

8 dia

lOdia

12 dia

6x6

8x8

10 x 10

12 x 12

5.000

31.000

6.000

40.000

3.000

11,000

24.000

4.000

14.000

30.000

2,000

8,000

16.000

31.000

3,000

10.000

20,000

40,000

5.000

9.000

19.000

6.000

12.000

24,000

3.000

6.000

12,000

4.000

8.000

16,000

9,000

NOTE. Safe capacity of each leg of shears or tripod is seven-eights of the value given for a gin pole.

11- 11. SHEARS

Shears are used to erect heavy machinery and bulky objects. Figure 11--11 shows the proper construction of shears. Shears must be guyed to hold their position and are designed to work inclined from the vertical.

u Material Maximum shear leg length is 60 times the least diameter of the leg. This ratio must be reduced for extremely heavy loads.

b Erection. Holes should be dug and the shear legs placed in them. This will prevent spreading of the legs. On hard surfaces, the legs should be level and lashed together to prevent spreading. Maximum spread at the base of the legs should not exceed V4 the height.

CLOVE HITCH

TACKLE SUNO

CLOVE HITCH

FRAPPINO

/ ^ CIOVK CHAT HITCH

'/ on All TO« / SHEAft LASHING

LOAD

TO POWER

Figure ¡1 — 11 Lashing for shears

288

11-12. GIN POLE

a. Description. A gin pole is dn upright spar, guyed at the top to hold it in a vertical or near—vertical position, and equipped with suitable hoisting tackle. It is easily rigged, moved, and operated (fig. 11—12).

b. Erecting. A gin pole 30 or 40 feet long may be raised easily by hand, but longer poles must be raised by supplementary figging or power equipment. Figure 11—12 shows the gin pole in position for operation, while the necessary rigging is illustrated in figure 11—13. The maximum allowable length is 60 times the minimum diarneter. Guys are 3 to 4 times the pole length.

BACK GUY FORE GUY

SIDE GUY

SIDE GUY

TO SOURCEÔf POWER

Figure 11 — 12 Gin pole ready for operation.

11-13. BOOM DERRICK

a. Rigging Booms are used on gin poles to lift loads at a distance from the base of the pole. The boom is two- thirds the length of the gin pole. For heavy loads, lower the butt of the boom to the ground. Raise if for lighter loads; however, it must not bear against the upper two—thirds of the pole.

b. Operations. It is a convenient means for loading and unloading trucks and flatcars, and for use on docks or piers. Figure 11 — 14 shows the boom derrick in position for operations.

CLEAT

CLOVE HITCH IN EACH GUY

DETAILS AT TOP OF GIN POLE

POLE

SEIZING

LASHING^*^

GUY

GUY

MOUSING SEIZING

CLEAT

TACKLE BLOCK POLE

CLEAT

DETAILS AT BASE OF GIN POLE

MOUSING

SNATCH BLOCK

l-'iguru 11 — 13. Lashing for gin pole

290

MAST

BOOM

LEAD

WEDGES

BOOM

z GREASE

HERE

3

Figure 11—14. Boom derrick.

I

11-14. GUY LINE TENSION FOR SHEARS AND GIN POLES

a. Tensions. The most stress on a guy line occurs when a guy line is in/ direct line with the load and. the structure. This would always be the case when a single guy line is used. To compute the tension on the single guy line (fig. 11 — 15), use the following formula:

(WL + ’/¿Ws)D

T_ Y Where:

T = tension in guy line

W|_ = weight of load

Wg = weight of spar

D

Y

b.

= drift distance

= perpendicular distance

Example Problem. Given:

Load Weight of spar Drift distance Y- distance

Solution:

2,500 lbs. 800 lbs.

10 feet 20 feet

f 2,500 + Vi (800)3 10

20 T = 1,450 lbs.

11-15. KNOTS

For the more common knots, see figure 11 — 16.

11-16. CHAINS

For safe working loads, see table 11—7.

11-17. HOOKS

For safe loads on hooks, see table 11 -8 and figure 11-17.

291

V

292

UNE OF

LOAD

WL REAR GUYLINE 9CT-^

FALL LINE

^ \J 'vl

Figure 11 —15. Computing tension in single guy lines

Table 11-7. Properties oj Chains ( Factor of Safety 6)

Size* Approximate weight per linear foot in pounds

Safe working load in pounds

Common iron

High grade iron

Soft steel

Special steel

1/4

3/8

1/2

5/8

3/4

7/8

1

1 1/8

1 1/4

1 3/8

0.8

1.7

2 5

4.3

5.8

8.0

10.7

12.5

16.0

18.3

512

1,350

2,250

3,470

5,070

7.000

9,300

9,871

12,186

14,717

563

1,490

2,480

3,810

5,580

7,700

10,230

10,858

13,304

16,188

619

1,650

2,630

4,230

6,000

8,250

10,600

11,944

14,634

17,807

1,240

3,200

5,250

7,600

10.500

14,330

18,200

21.500

26,300

32,051

'SIZE LISTED IS THE DIAMETER IN INCHES OF ONE SIDE OF A LINK.

NAME ILLUSTRATION USE

-.STANDING END-'

St D^) ^ _ *S'/

RUNNING END —^

JOIN TWO ROPES OF SAME SIZE. <WILl NOT SLIP, BUT WILL DRAW

TIGHT UNDER STRAIN.) TO END BLOCK LASHING.

DOUBLE

SHEET

BEND

JOIN WET ROPES, OF UNEQUAL SIZE,

OR ROPE TO AN EYE.l(WILL NOT SLIP OR DRAW TIGHT UNDER STRAIN.)

FORMA LOOP.(WILL NOT SLIP UNDER STRAIN AND IS EASILY UNITED.)

f RUNNING EN¿

TIMBER

HITCH

LIFTING OR OR AGOING HEAVY

TIMBERS. (IS MORE EASILY

CONTROLLED IF SUPPLEMENTED

BY HALF HITCHES.)

STANDING END

CLOVE

HITCH

FASTEN ROPE TO PIPE, TIMBER, OR

POST. (IT IS USED TOJTART AND

FINISH ALL LASHINGS AND MAY BE

TIED AT ANY POINT IN ROPE.)

SHEEP

SHANK

SHORTEN ROPE OR TAKE LOAD OFF WEAK SPOT IN ROPE.

RtHMMAM't

UNO

TO FASTEN CABLE OR ROPE TO ANCHOR.

Figure 11—16. Knots.

293

294

Table 11-8 Safe Loads on Hooks

DIAMETER OF

METAL A.*

IN.

INSIDE DIAMETER OF EYE B.

IN.

WIDTH OF OPENING C

IN.

LENGTH OF HOOK D,

IN.

SAFE WORKING CAPACITY OF HOOKS,

LB.

11/14 3/4 7/8

1 1 1/8 1 1/4 1 3/8 1 1/2 1 5/8 1 7/8 2 1/4 2 3/8 3

7/8 1 1 1/8 1 1/4 1 3/8 1 1/2 1 5/8 1 3/4 2 2 3/8 2 3/4 3 1/8 3 1/2

1 1/14 1 1/8 1 1/4 1 3/8 1 1/2 1 11/14 1 7/8 2 1/14 2 1/4 2 1/2 3 3 3/8 4

4 15/14 5 13/32 4 1/4 4 7/8 7 5/8 8 19/32 9 1/2

10 11/32 11 27/32 13 9/32 14 13/14 14 1/2 19 3/4

1,200 1.400 2.400 3.400 4,200 5.000 4.000 8.000 9.400

11,000 13,400 17.000 24.000

•FOR REFERENCE TO A, B, C, OR D, SEE FIGURE 11—17. NOTE: FORMULA FOR SAFE WORK LOAD FOR HOOKS:

2 2 T (TONS) = D (IN ).

EYE

. A THROAT

MOUTH

Figure 11-17 Slip hook

CHAPTER 12

UTILIZATION OF HEAVY EQUIPMENT

12—1. GENERAL

a. This chapter should be used as a general guideline when estimating construction equipment requirements and production. Production estimates given are based on average conditions, and may vary considerably with actual job site conditions. More detailed information may be found in TM's 5—331 A through E.

b. Good jobsite management requires constant monitoring of the operation, adjusting resources based on actual production to insure maximum utilization of equipment, and proper sequence and coordination of all related operations.

12-2. CONSTRUCTION CLEARING

Crawler tractor clearing production. See table 12—1.

12 - 3. STRIPPING, EXCAVATING, AND HAULING

a. Equipment Selection and Production. See table 12—2.

b. Crawler Tractor/Dozer (1) Crawler tractors are the most economical equipment for moving

earth for short distances (0 to 300 feet). A medium—sized dozer has a blade capacity of 5.0 cubic yards and will consume approximately 9 gallons of fuel per hour of normal operation.

(2) Dozer production may be maximized by slot dozing, blade—to—blade dozing, downhill dozing, and ripping the soil prior to dozing.

(3) Dozers should be used to push—load towed scrapers by one of the following procedures.

(a) Backtrack loading. The dozer pushes the scraper until loaded, backs through the area just cut, positions itself behind the second loader, and repeats the loading cycle.

295

296

Table 12-1. Estimates for Area Clearing*

Production Estimates in Acres per hour

Vegetation Density

Equipment Light Medium Heavy

Medium size dozer w/bull blade .40 .20 .10

Medium size dozer w/tree dozer blade 2.50 1.25 .77

•Reference DA PAM 525-6, June 1970.

(b) Shuttle loading After the dozer push-loads the first scraper, another scraper is positioned so the dozer can reverse direction and load the second scraper while traveling in the opposite direction.

(c) Chain loading In long cuts, the dozer push-loads the first scraper, then moves behind and pushes the second scraper which is moving in the same direction and adjacent to the first.

c. Scraper Production. Scraper production can be maximized by downhill loading, straddle loading, and ripping the soil prior to loading.

d. Haul Roads. All haul roads should be maintained with a grader to lower rolling resistance and insure that all loaded units can leave the cut area as fast as possible.

12-4. LIFTING AND LOADING

a. Power Shove! and Dragline Production. See table 12—3. b. Scoop Loader Production See table 12-4.

c. Soil Conversion Factors. See table 12—5.

Table 12-2. Stripping. Excavating, and Hauling ■

Production Estimates in Bank Cubic Yards Per Hour

Distance

15 ft

30 ft

50 ft

75 ft

100 ft

150 ft

300 ft

500 ft

1000 ft

1500 ft

3000 ft

1 mi

2 mi

3 mi

5 mi

EQUIPMENT

Dozer Med, Ft

1600

870

512

350

263

175

87

R/T Tractor Scraper - 18 Cu Yd

259

288

288

240

183

226

181

149

97

62

34

24

Scraper- 24 Cu Yd

345

374

374

354

336

285

225

182

114

71

39

27

17

'AT HAUL DISTANCES GREATER THAN 3000 FT, THE POSSIBILITY OF USING A LOADER AND DUMP TRUCKS SHOULD BE EVALUATED (SEE SECTION 12-4-d). IF LOADERS ARE USED, A DOZER IS NORMALLY REQUIRED TO STOCKPILE MATERIAL.

297

298

Tuble 12- 3 Power Shovel and Dragline Prodnciioir

PRODUCTION ESTIMATES IN BANK CUBIC YARDS PER 60 MINUTE HOUR

ATTACHMENT/TYPE

MATERIAL

POWER SHOVEL

BUCKET SIZE

CU. YD.

JOB AND MANAGEMENT FACTORS

POOR GOOD EXCELLENT

MOIST LOAM-

LIGHT SANDY CLAY 3/4

2

66

185

124

266

139

298

SAND AND GRAVEL 3/4

2

61

172

116

248

130

277

GOOD COMMON EARTH

3/4

2

70

156

101

225

113

252

CLAY. HARD, TOUGH 3/4

2

57

138

83

199

95

223

CLAY, WET, STICKY 3/4

7

36

96

53

139

59

155

ROCK, WELL BLASTED 3/4

2

49

120

71

1/3

80

193

ROCK, POORLY BLASTED

3/4

2

26

83

38

120

42

134

MOIST LOAM-

LIGHT SANDY CLAY

3/4

2

68

138

109

223

SAND AND GRAVEL 3/4

2

65

133

94

191

105

214

GOOD COMMON EARTH 3/4

2

55

120

79

173

CLAY. HARD. TOUGH 3/4

2

47

101

68

146

76

164

CLAY, WET, STICKY 3/4

2

29

75

41

109

46

122

•REF: TM 5-331-B, May 1968 AND PSCA TECHNICAL BULLETIN NO. 1

••BASED ON SUITABLE DEPTH OF CUT FOR MAXIMUM EFFECT AND A SWING ANGLE OF 90° . TO CONVERT TO LOOSE CUBIC YARDS, USE

SOIL CONVERSION FACTORS FROM TABLE 12-5.

Table 12 4. Scoop Loader Production

Production Estimates In Loose Cubic Yards Per 60—Minute Hour

SAE Rated Bucket Capacities

1 Vi cu yd

2Vi cu yd

5 cu yd

Cycle time in seconds

20

270

450

900

30

180

40

135

300

600

225

450

50

108

180

360

60

90

80

67

100

54

150

300

112

225

90

180

120

45

75

150

140

38

64

128

160

34

56

112

180

30

200

27

50

100

45

90

Table 12—5 Soil Conversion Factors (Estimated)

Soil Type Initial Soil

Condition

Converted to:

In Place Loose Compacted

Sand

In Place

Loose .90

Compacted 1.05

1.11

1.17

.95

.86

Loam

In Place

Loose .80

Compacted 1.11

1.25

1.39

.90

.72

Clay

In Place

Loose .70

Compacted 1.11

1.43

1.59

.90

.63

Rock (blasted)

In Place

Loose .67

Compacted .77

1.50

1.15

1.30

.87

299

300

d. Estimating Dump Truck Requirements. The following formula is used to make a preliminary estimate of the number of trucks required to keep loading equipment in operation at maximum capacity.

1 + travel time (min) N

loading time (min) N = number of trucks required (1) ¿The travel time is the time that is required for a hauling unit to

complete one cycle of operation and may be determined by actual measurement or by estimation. The time required for a loaded dump truck to pull away from the loading equipment, travel to the site where the material is required, unload, return to the loading unit, and be reloaded is one complete cycle.

(2) The loading time is the time required for the loading equipment to actually load the truck. This is determined by dividing the truck size (in cubic yards) into the loading unit production (in cubic yards per hour) to get loads per hour. Divide loads per hour into 60 to obtain loading time in minutes.

(3) Example: How many 5 cubic- yard trucks would be required to haul 150 cubic yards per hour with a travel cycle time of 30 minutes?

Solution:

150 cu yds/hour = 30 loads per hour

5 cu yds/load 60 — = 2 minutes loading time 30

N = 1 + travel

loading time (min) 2 N = 16 trucks

12-5. GRADING AND DITCHING

a Production Capabilities of Graders See table 12—6.

Table 12—6 Production Capabilities of Graders

Operation Rate

Per Hour Unit Conditions

Ditching 250 150 85

Cu Yd Cu Yd Cu Yd

"V” ditching, easy digging "V" ditching, medium digging “V" ditching, hard digging

Grading Mile Digging side ditches and shaping crown, 4 round trips required

Subgrade Preparation 400 Sq Yd Scarify and shape

Base Course Preparation

200 450

Cu Yd Cu Yd

Spreading material Shaping surface

Surface Treatment 150 Sq Yd

Mixing in place 2 inches of bituminous material

NOTE For working distances up to 1000 feet, graders should back up to beginning of project. For longer distances, turn grader around.

b Steps in hasty road construction: (1 ) Marking cut. Place right front wheel in line with ditch stakes. Set

mold board at outside of right front wheel and make a 3 to 4 Inch cut along stakes.

(2) Ditching cut. Place right front wheel In marking cut. Adjust mold board so leading edge is In line with and behind right front wheel. Make cuts as deep as possible.

(3) Moving windrow Angle mold board and move windrow from ditch cut to center of road.

(A) Level windrow Make road surface and crown. (5) Slope. Slope banks to prevent erosion. (6) Police. Clean and clear ditches.

301

-■»K

302

12-6. COMPACTION

a. Selection of Compacting Equipment The type of soil to be compacted generally governs the type of compactor to be used. For compaction purposes, soils may be divided into two major types; (1) cohesionless, or granular soils, and (2) cohesive soils. Granular soils generally limit the compactors to pneumatic-tired, vibratory, or (rarely) smooth drum compactors. Cohesive soils generally require a footed type compactor.

b Production Capabilities of Sheepsfoot Rollers. See table 12—7. c. Limitations. A compaction test strip is necessary to determine the

depth of lift and the required number of passes. Compactor production may limit cut and fill operations, and should be determined prior to calculating haul unit requirements.

Table 12—7. Compacting Fill—Sheepsjoot Roller

Production Estimates in Cubic Yards Per Hour

Equipment

Number of passes

10

Sheepsfoot roller 880 628 488 440

12-7. PRODUCTION AND JOB DURATION ESTIMATION

General estimates of production for engineer construction equipment may be obtained in the following manner:

a. Select an efficiency factor (E) from table 12—8.

Table 12—8. Efficiency Factors

Type Tractor

Working Houn

Efficiency Factor

Day Operation Track

Wheel

50 min/hr

45 min/hr

0.83

0.75

Night Operation Track

Wheel

45 min/hr

40 min/hr

0.75

0.67

b. Estimate the cycle time for the operation in question. Cycle time is a combination of fixed time and variable time. Fixed time is the time required for positioning, loading, and unloading, and is best determined by actual measurement. Variable time is normally the hauling or travel time. Travel time may be calculated by the following equation:

travel distance (ft) Dozer Travel time (min)

speed (mph) x 88 Round trip distance must be used to determine travel time both ways. Variable time plus fixed time would equal cycle time.

c. Determine the equipment capacity. d. If necessary, convert the equipment capacity to bank cubic yards (See

table 12-5). e. Estimate hourly production (P) by the following formula. (Scraper

Production)

P = capacity x 60 min/hr x E (eff factor)

cycle time (min) Estimate time required by the following formula:

total job requirement in machine—hours

P x N N = Number of like equipment units used. P = Hourly production for one unit.

Time (hours) = ■

303

304

CHAPTER 13

FIELD SANITATION

13-1. SANITATION FACILITIES

For details on field sanitation see FM 21 — 10.

13- 2. WASHING FACILITIES

a. Hand-washing devices should be set up near latrines and kitchens. See figure 13—1.

I WATER

* 1

Figure 13—1. Hand-washing device, using number 10 can.

b. Showers should be set up whenever possible for personal hygiene and ' morale. See figure 13—2.

13-3. WASTE DISPOSAL

a. Latrines

(1) Size should be adequate to take care of at least 8 percent of the unit at once. Sixteen feet of straddle trench in four-foot sections, or two deep pit latrines with four-hole latrine boxes, is adequate for a 100-man unit.

(2) Locate at least 100 meters from kitchen, outside the cantonment area but inside the perimeter, and convenient to tents.

(3) See figures 13-3, 13-4, and 13-5.

Figure 13-2 Shower unit, using metal drums

305

306

HOLE APPROX 9 » iriiiipsi URINE

DCf ICCf OR STRIP

> .STOP SIOCK

' 1

Figure J S-S Box latnne for 50 men

SHOVIL

TISSUE

CM âX’IDE DEEP

WASHING DEVICE NO TO CANS MAY

BE PLACED OVER TISSUE TO PROTECT FROM WEATHER

Figure 13-4 Straddle trench latrine for ¡00 men. with hand-washing de vice.

REMOVEA8LE SCREEN TO CATCH TRASH

WASTE OIL COVERING WATER

GROUND LINE

NOT! USE A SOUIIT CAN DAILY TO SPRAY OIL ON CATCHSCREEN AND AROUND DRUM

TO KEEP FLIES AND OTHER INSECTS FROM OATHERINO. OIL-WILL CURTAIL ANY BAD ODORS

(4) Police the latrines properly and maintain a good fly—control program in the entire camp area to prevent fly bredding and to reduce odors.

(a) Keep the lids to the latrines seats closed and all cracks sealed. (h) Scrub the latrine seats and boxes with soap and water daily. (f) Spray the inside of the shelters with a residual insecticide twice

weekly. If a fly problem exists, also spray the pit contents and the interior of the boxes twice weekly with a residual insecticide. Using lime in the pits or burning out the pit contents, except in burn- out, is not effective for fly or odor control. Therefore, these methods are not recommended.

(5) At such time as a latrine pit becomes filled with wastes to a point 1 foot from the surface or is to be abandoned, remove the latrine box and close it as follows:

(a) Using an approved residual insecticide, spray the pit contents, the side walls, and the ground surface extending 2 feet from the side walls.

(b) Fill the pit to the ground level with successive 3—inch layers of earth, packing each layer down before adding the next one; then mound the pit over with at least 1 foot of dirt and spray it again with insecticide. This prevents any fly pupa, which may hatch in the closed latrine, from getting out.

/■'¡Hurt' i.i- .5 Urinoil

307

308

(c) Place a rectangular sign on top of the mound. The sign must indicate the type of pit and the date closed as well as the unit designation in non- operational areas.

(6) When high water tables preclude the use of pit latrines, burn out latrines may be used. Half of a 55- gallon drum or barrel is installed under each hole in the latrine box (fig. 13--6). The drum is removed daily, fuel oil is added and the contents are burned to a dry ash. An inch of diesel fuel is added for insect control before replacing the drum in the latrine box.

b. Garbage Pits. ( 1 ) Size should be at least 4 feet square and 4 feet deep. (2) Locate as far from kitchen as possible, outside camp area if

oractical. (3) When filled to within 30- cm of ground level, or when abandoned,

fill pit in and mound over with 60—cm overburden of compacted earth.

OR BARREL ^—a/

Figure 13~6 Burn-out latrine.

(4) Liquid kitchen wastes should never be dumped into garbage pits as this precludes effective burning out and shortens utilization for the pit.

c Soakage Pits Liquid Kitchen wastes should be disposed of in soakage pits. These should be located in the kitchen area. The soakage pit may be constructed the same as the urinoil (fig. 13—5) except that a grease trap must be provided (fig. 13—7) and drainage provided to prevent surface runoff from filling up the pit. In constructing the pit, omit pipes and heve drainage from grease pipe drain into pit.

PREFORATED WOODEN BOX WITH GRASS FOR STRAINING

OUTLET PIPE

Figure ¡3-7 Ba/fle grease trap (barrel type).

309

CHAPTER 14

RECONNAISSANCE

14-1. ROUTE RECONNAISSANCE

a Definition Route reconnaissance provides information to aid in route selection for the movement of troops, equipment, and supplies. It is governed by the same fundamentals that apply to all reconnaissance and is made on the ground, but should be supplemented by air reconnaissance when practicable. Information sought in this type of reconnaissance includes:

(1) Nature of terrain. (2) Existing roads and their characteristics, including loadbearing

capabilities. See TM 5—330 for more detailed information. (3) Obstructions. (4) Bridges and other stream crossing means (5) Tunnels.

b Mission. Route reconnaissance must consider the mission of the parent unit. Reconnaissance factors include the weight, width, and height of the vehicles that will be used, the classification of these vehicles, the approximate number of each class to be moved per hour, and the approximate length of time the route will be used.

c. Report. A reconnaissance report should be accurate, concise, and clear. The preferred method of preparation is in simplified map form or overlay (fig. 14—1), using symbols (table 14—1) to show the limiting features. A route reconnaissance report is accompanied by an engineer reconnaissance report form, a road reconnaissance report, and bridge, tunnel, ferry, and ford reconnaissance reports as needed. (Fig. 14—2). Military sketches of limiting features, local maps, and photographs of significant factors (terrain, roads, tunnels, bridges, ferries, fords, and so forth) support the route report.

41

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25

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A

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311

Table 14—1. Overlay Symbols

SYMBOLS FOR USE IN THE RECONNAISSANCE REPORT SYMBOL

3/1SM

DESCRIPTION A CRITERIA

SHARP CURVE (OB) ANY RADIUS LESS THAN OR EQUAL TO 30 METERS. HOWEVER. ANY CURVE GREATER THAN 30 METERS,BUT LESS THAN 45 METERS IS REPORTABLE

SERIES OF SHARP CURVES. THE FIGURE TO THE LEFT INDICATES THE NUMBER OF CURVES. THAT TO THE RIGHT, THE MINIMUM RADIUS OF CURVATURE IN METERS.

ÏV £V

\z‘ iiv

STEEP GRADES- (OB) ANY GRADE 7% OR HIGHER. ACTUAL % OF GRADE WILL BE SHOWN ARROWS ALWAYS POINT UPHILL, AND LENGTH OF ARROW REPRESENTS LENGTH OF GRADE IF MAP SCALE PERMITS

CONSTRICTION (OB) ANY REDUCTION IN THE TRAVELED WAY BELOW THE STANDARDS OF TABLE 14—3. THE FIGURE TO THE LEFT INDICATES THE WIDTH OF THE CONSTRICTION; THAT TO THE RIGHT, THE TOTAL CONSTRICTED LENGTH, BOTH IN METERS

ARCH TYPE

TRAVEL / v MAXIMUM / MINIMUM WAY / \ OVERHEAD / OVERHEAD

WIDTHA ACLEARANCE/ CLEARANCE

UNDERPASSES. SHOW SHAPE OF STRUCTURE

(OB) WHEN OVERHEAD CLEARANCE IS LESS

THAN 4.30 M OR WHEN THE TRAVELED

RECTANGULAR

TRAVEL WAY

WIDTH OVERHEAD CLEARANCE

WAY IS BELOW THE STANDARDS OF TABLE

14—2. SEE FIG 14—2, NOTE 4.

Table ¡4—1. Overlay Symbols(Con't)

BYPASS > " CONDITIONS

TRAV

SERIAL NUMBER (NOTE 1)

TRAVELED WAY WIDTH (NOTE 71

DESCRIPTION « CRITERIA

TUNNEL. (INCLUDES MANMADE SNOWSHEDS). SHOW SHAPE OF STRUCTURE. (OB) WHEN

OVERHEAD CLEARANCE IS LESS THAN 4.3ÛM

OR WHEN THE TRAVELED WAY IS BELOW THE

STANDARDS OF TABLE 14—2 SEE FIG 14—2,

NOTE 4.

BYPASSES ARE LOCAL ALTERNATE ROUTES

WHICH ENABLE TRAFFIC TO AVOID AN

OBSTRUCTION. BYPASSES ARE CLASSIFIED AS

EASY, DIFFICULT. OR IMPOSSIBLE. EACH TYPE

BYPASS IS REPRESENTED SYMBOLICALLY ON

THE LINE EXTENDING FROM THE SYMBOL TO

THE MAP LOCATION AND DEFINED AS FOLLOWS:

BYPASSES EASY. THE OBSTACLE CAN BE

CROSSED WITHIN THE IMMEDIATE VICINITY BY

A US 2.5 TON TRUCK (OR NATO EQUIVALENT)

WITHOUT WORK TO IMPROVE THE BYPASS

BYPASS DIFFICULT THE OBSTACLE CAN BE

CROSSED WITHIN THE IMMEDIATE VICINITY,

BUT SOME WORK WILL BE NECESSARY

TO PREPARE THE BYPASS

r T_

BYPASS IMPOSSIBLE THE OBSTACLE CAN ONLY

BE CROSSED BY ONE OF THE FOLLOWING METHODS.

(1) REPAIR OF ITEM; I E . BRIDGE

(2) NEW CONSTRUCTION

(3) DETOUR USING AN ALTERNATE ROUTE WHICH CROSSES THE OBSTACLE SOME DISTANCE AWAY

312a

312 b

Table 14—1. Overlay Symbols (Con 'll

DESCRIPTION & CRITERIA

RAILROAD (RR| LEVEL GRADE CROSSING

PASSING TRAINS WILL INTERRUPT TRAFFIC FLOW THE FIGURE INDICATES OVERHEAD

CLEARANCES

- .<*- Frï? H, Jr Ja

'SAW

FORD ALL FORDS ARE CONSIDERED AS

OBSTRUCTION (OB) TO TRAFFIC

TRAFFICABILITY CONDITIONS SHOWS IN

TABLE 14-6 INDICATE CONDITIONS ON

BOTH APPROACHES SEE FIGURE 14-2,NOTE 3

TYPE OF FORD

VEHICULAR P - PEDESTRIAN

SEASONAL LIMITING FACTORS

X - NO SEASONAL LIMITATION EXCEPT

FOR DURATION SUDDEN FLOODING

V - SIGNIFICANT SEASONAL LIMITATIONS

APPROACH CONDITIONS

DIFFICULT EASY

NATURE OF BOTTOM

M - MUD C - CLAY S - SAND

G-GRAVEL R - ROCK P - ARTIFICIAL PAVING

/ (NOTE 1)

SERIAL TYPE (NOTE 3)

WVVw— s W/T /

i!IV DEAD W/1

CAPACITY

TURN AROUND

FERRY ALL FERRIES ARE CONSIDERED

AS OBSSTRUCTIONS (OB| TO TRAFFIC

APPROACH CONDITIONS

DIFFICULT EASY

TYPE OF FERRY

V — VEHICULAR FERRY

P - PEDESTRIAN FERRY

Table 14—Î. Overlay Symbols (Con't)

SYMBOL DESCRIPTION A CRITERIA

ROUTE DESIGNATION CIVIL OR MILITARY

ROUTE DESIGNATION WRITTEN IN

* AMÂ

? Oo o o •00° o OO

AO

VA°V

PARENTHESES ALONG ROUTE.

<1)

(2)

OFF—ROUTE MOVEMENT (TURN OFF'S)

A CONCEALMENT (ARROWS POINT TO LEFT

OR RIGHT OF ROAD WHERE TURN OFF

EXISTS)

( 1 > POSSIBLE TURN OFF

(2) TRACKED VEHICLE TURN OFF

WITH CONIFEROUS CONCEALMENT

()) O) WHEELED VEHICLE TURN OFF

WITH DECIDUOUS CONCEALMENT.

(4) (4) POSSIBLE TURN OFF IN MIXED

CONCEALMENT.

NOTE

RECORD DISTANCE ON STEM OF ARROWS

WHEN OFF ROUTE MOVEMENT IS LESS

THAN ONE KM

313

314

Table 14—Î. Overlay Symbols (Con’t)

DESCRIPTION & CRITERIA

LIMITS OF SECTOR LIMITS OF

RECONNOITERED SECTOR OR OF ROUTE HAVING

THE SAME ROAD CLASSIFICATION FORMULA

CULVERT REGARDLESS OF TYPE. LENGTH.

SIZE. OR NUMBER OF PIPES IN THE SYSTEM

OR / S

CRITICAL POINTS: ARE USED AS NUMBERED KEYS TO DESCRIBE IN DETAIL, ON ATTACHED RECONNAISSANCE FORMS OR DOCUMENTS, THOSE FEATURES THAT CANNOT BE ADEQUATELY COVERED BY OTHER

RECONNAISSANCE SYMBOLS ON THE OVERLAY.

\ \ \

(I) (2) (3)

OBSTACLES (ROAD BLOCKS. CRATERS.

BLOWN BRIDGES, LANDSIDES, ETC.):

1. PROPOSED OBSTACLE

2. PREPARED BUT PASSABLE OBSTACLE

3. COMPir 'n OBSTACLES

UNKNOWN OR DOUBTFUL INFORMATION:

USED IN ALL SYMBOLS WHERE INFORMATION

IS NOT KNOWN, OR DOUBTFUL

Table ¡4-1 Overlay Symbols (Con !)

ENGINEER RESOURCE SYMBOLS

❖ SAWMILL

X ELECTRICAL SUPPLY EQUIPMENT

LUMBER YARD © WATER POINT (MILITARY)

AGGREGATE (INCLUDING ¿ GRAY EL,SLAG) ETC.

FORESTRY EQUIPMENT

SAND PAINT

IRON & STEEL STOCK

n GYPSUM ¡L & LIME ]/ PRODUCTS

WIRE STOCK H CEMENT

CONCRETE PRODUCTS

4>f

T_

MOBILE HEAVY CONSTRUCTION EQUIPMENT

QUARRING EQUIPMENT

POWERED HAND TOOLS

BRICK & J=p-, OTHER CLAY

PRODUCTS

A FACTORIES

ASPHALT a BITUMINOUS STOCK

UTILITY (CIVILIAN) 3®C WATER

-j(5)C GAS a(i)C ELECTRIC

CORDAGE, NETS a YARN

315

316

FULL BRIDGE SYMBOLS fHOU 4)

\ OVERALL LENGTH

k BYPASS CONDITION

ONE WAY

CLASS ONE WAY TRAFFIC

MILITARY

NOTE

WIDTH QF

TRAVELED WAY BRIDGE LOCATION

ONE

CLASS CLASS TWO WAY

ABBREVIATED BRIDGE SYMBOLS

(WHEN USED OVERLAY MUST BE ACCOMPANIED

WITH DA FORM 1249 OR DETAILED REPORT |

E

ONLY SINGLE FLOW TRAFFIC IS REPRESENTED IN ABBREVIATED BRIDGE SYMBOLS FOR BRIDGES WITH

SEPARATE TRACKED AND WHEELED VEHICLE CLASSIFICATION. ONLY THE LOWER CLASSIFICATION IS

SHOWN IF A BRIDGE HAS MORE THAN ONE CLASSIFICATION. THE CLASSIFICATION NUMBER SHOWN IS

ASTERISKED l*l AND FULL CLASSIFICATION IS SHOWN IN THE ACCOMPANYING REPORT

NOTE 1 A SERIAL NUMBER IS ASSIGNED TO EACH BRIDGE TUNNEL FORD AND FERRY

SERIAL SERIAL NUMBERS MUST NOT BE DUPLICATED ON ANY ONE MAP SHEET OVERLAY OR

NUMBERS DOCUMENT

NOTE 2 IF SIDEWALKS EXIST AND WILL PERMIT THE PASSAGE OF WIDER VEHICLES.

TRAVELED SYMBOLIZE THE SIDEWALKS AND RECORD THE WIDTH AS THE TRAVELED

WAY WIDTH WAY/TOTAL WIDTH

NOTE 3 THE LEFT AND RIGHT BANKS OF A STREAM ARE DETERMINED BY LOOKING IN THE BANK RIGHT DIRECTION OF THE CURRENT DOWNSTREAM

ORIENTATION

NOTE 4 ANY OVERHEAD CLEARANCE LESS THAN THE STANDARDS OF TABLE 14—2 IS

CRITICAL UNDERLINED ANY WIDTH OF A BRIDGE WHICH IS LESS THAN THE STANDARDS OF

DIMENSIONS TABLE 14-2 IS UNDERLINED THE TWO WAY CLASS OF ANY TWO LANE BRIDGE IS DOWNGRADED IF THE WIDTH OF THE BRIDGE IS LESS THAN THE STANDARDS OF

TABLE 14 - 3 THE WIDTH OF THE TRAVELED WAY OF TUNNELS OR UNDERPASSES WHICH IS LESS THAN THAT OF THE OUTSIDE ROUTE IS UNDERLINED

Figure 14-2. Bridge reconnaissance symbols

d. Overlay. Important features to be included on an overlay are shown below. The first five items are required:

( 1 ) Two grid references. (2) Magnetic north arrow. (3) Route drawn to scale. (4) Title block. (5) Route classification formula. (6) Length (in kilometers) between well marked points. (7) Curves having radii of less than 45 meters or 150 feet. (8) Steep grades, with their maximum gradients in percent, and length

of any grade of 5 percent or greater. (9) Road width of constrictions (bridges, tunnels and so forth), with

the widths and lengths of the traveled ways in meters. (10) Underpass limitations, with their limiting heights and widths in

meters. (11) Bridge bypasses, classified as easy, difficult, or impossible. (12) Civil or military road numbers, or other designations. (13) Feasibility of driving off roads, including shoulders. (14) Location of fords, ferries, and tunnels including limiting

information. (15) Causeways, snowsheds, and galleries which constitute an

obstruction to traffic should be included in the route reconnaissance report. Limit the data to clearance and load—carrying capacity. If possible, support the information with photographs or sketches of each structure. Also, include enough descriptive information to permit an evaluation concerning the strengthening or removal of these structures.

e. Route Classification Formula. It is a standardized sequence pf: (1) Width. Narrowest width of the route expressed in meters (m) or

feet (ft). (2) Route type. Determined by worst section of the route.

(a) (X) A ll-weather. Any road which, with reasonable maintenance, is passable throughout the year to a volume of traffic never appreciably less than its maximum capacity. This type of road has a waterproof surface and is only slightly affected by rain, frost, thaw, or heat. At no time is it closed to traffic due to weather effects other than snow blockage. Examples of this category are concrete, bituminous, brick, or stone.

318

(b) (Y) Limited all—weather Any road which, with reasonable maintenance, can be kept open in bad weather to a volume of traffic which is considerably less than its normal capacity. This type of road does not have a waterproof surface and is considerably affected by rain, frost, or thaw. Examples of this category are crushed rock or waterbound macadam, gravel, or lightly metaled surface.

(c) (Z) Fair weather. A road which becomes quickly impassable in bad weather and which cannot be kept open by normal maintenance. This type of road is seriously affected by rain, frost, or thaw. Examples of this type are natural or stabilized soil, sand or clay, shell, cinders, or disintegrated granite.

(3) Military route classification. Normally it is the lowest one-way bridge load classification along the route. If no bridges exist the worst section of the route governs.

(4) Obstructions (OB). Any factors which restrict tye type, amount, or speed of traffic flow, e.g., overhead clearances, traveled way widths, steep gradients, sharp curves, ferries, and fords which may cause obstructions, denoted by (OB) in the route classification formula. Consult tables 14—1 and 14—2 for limiting values.

(5) Special conditions. Snow blockage (T) and flooding (W) are used when the condition is regular, recurrent, and serious.

Example: 6.7 m Y 30 (OB) (W). Route is 6.7 meters wide, limited all-weather

route with a load carrying capacity of class 30. Obstructions do exist and route is subject to flooding.

14 - 2. ROAD RECONNAISSANCE

Road reconnaissance is performed in order to obtain information on road classification, primarily in support of selecting a route, and to report changes to existing maps for dissemination in the theater of operations. Its purpose is to find out the quantity and kinds of loads that a road can accommodate in its present condition. It may also include estimates of the effort necessary to improve and/or maintain a road subjected to specific traffic for a definite period of time. An example of a road reconnaissance report (DA Form 1248) is shown in figures 14—3 and 14—4.

Table ¡4—2. Critical Dimensions oj Route Classijication

-ROUTE WIDTHS

TRAFFIC FLOW POSSIBILITIES

SINGLE FLOW

DOUBLE FLOW

WIDTHS FOR W HEELED VEHICLES

S SO METERS TO

7 METERS

n8FT TO

23 FT

OVER 7

METERS

23 FT

WIDTHS FOR TRACKED

VEHICLES

6 METERS TO

g METERS

I 19 1/2 FT TO

26 FT

OVER 6

METERS

i 26 FT

-MINIMUM ROUTE WIDTHS FOR BRIDGES

BRIDGE CLASSIFICATION

MINIMUM WIDTH BETWEEN

CURBS

ONE LANE

¡METERS TWO LANE

METERS

4-12

13-30

31-60

6) 100

2 7S(9'-0)

3.35(H'-0"'

4 00( 13'-2")

4 S0( 14'-9")

S SOI 18'-0''l

S SOI I8‘-0"I

7.301 24'-0" 1

0.2O{27'-O")

MINIMUM OVERHEADCLEARANCES FOR BRIDGES

BRIDGE CLASSIFICATION

MINIMUM

OVERHEAD CLEARANCE

UP TO 70

ABOVE 70

4.30 METERS (14 FT 0* IN:

4.70 METERS < 15 FT -6 IN-

MEASURING WIDTH OF ROADWAY AND HORI- ZONTAL AND VERTICAL CLEARANCES FOR TUNNELS. UNDERPASSES. AND THROUGH

TRUSS BRIDGES

4a

i MINIMUM OVERHEAD

CLEARANCE MEASURED VERTICALLY FROM EDGE

OF TRAVELED WAY

7 EFFECTIVE WIDTH OF THE TRAVELED WAY CURB TO

CURB

3 HORIZONTAL CLEARANCE IS THE MINIMUM WIDTH MEASURED AT LEASE FOUR FEET ABOVE THÉ TRAVELED

WAV

4 MAXIMUM OVERHEAD

CLEARANCE. IS THE MIN- IMUM DISTANCE BETWEEN

THE TOP OF THE TRAVELED WAY AND THE LOWER EDGE OF THE OVERHEAD OR ANY

OBSTRUCTION BELOW

THE OVERHEAD. SUCH AS

TROLLEY WIRES OR ELEC-

TRIC LIGHT WIRES

4a RISE OF ARCH RADIUS OF CURVED PORTIONl

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Figure 14—4. Road reconnaissance report (back).

321

322

a Information Required. ( 1 ) Local name of road and/or designation. (2) Location of road by map grid reference. (3) Obstructions, which include, among other items, underpasses,

fords, large tree limbs, craters, projecting buildings, areas subject to inundation, and so forth.

(4) Bridge locations, (para 14- 3). (5) Tunnel locations, together with their lengths, widths, and heights,

(para 14-5 and table 14—1.) (6) Snowshed locations and estimated coverage.

b. Road Classification Formula. The road classification formula is expressed in a standardized sequence of a prefix, limiting characteristics at present, width of the traveled way, combined width of the traveled way and the shoulders, road surface material, length, obstructions, and special conditions.

(1) Prefix. The formula is prefixed by the letter "A" if there are no limiting characteristics. The letter "B" is the prefix if there are any limiting characteristics.

(2) Limiting characteristics Symbol Curves (radius 30m or less) c Gradients (7% or greater) g Drainage (inadequate) d Foundation (unstable) f Surface Condition (rough) s Chamber or superelevation (excessive) i An unknown or undetermined characteristic is represented by a

question mark following the symbol of the feature to which it refers, e.g., (d?).

(3) Width Width of the traveled way is expressed in meters followed by a slash and the combined width of the traveled way and the shoulders, e.g., 14/16.

(4) Road surface material Road surface material is expressed by a letter symbol as follows:

Symbol Material

v

P

n

pb

r

rb

b

k kb nb

Concrete Bituminous or asphaltic concrete (bituminous plant mix). Bituminous surface treatment on natural earth, stabilized soil, soil, sand—clay or other select material. Used when type of bituminous construction cannot be determined. Bituminous surface on paving brick or stone Bitumen -penetrated macadam, water—bound macadam with superficial, asphalt, or tar cover. Paving brick or stone Waterbound macadam, crushed rock, or coral Gravel or lightly metaled surface Natural earth, stabilized soil, sand—clay, shell, cinders, disintegrated granite, or other select material Varipus other types not mentioned above (indicate length when this symbol is used).

(5) Length. Length of road (in km) may or may not be shown. If shown place in parentheses, e.g., (7.2 km).

(6) Obstructions. Expressed as (OB) when existing on road, e.g., overhead clearance less than 4.30 m, reduction in the traveled way widths below the standards of table 14—2, gradients of 7 percent or greater, and curves with radii of 30 m (100 ft) or less.

(7) Special conditions Snow blockage (T) and flooding (W) are used when the condition is regular, recurrent, and serious.

Bcgd (f?)s 3.2/4.8 nb (4.3 km) (OB) (T): Road has limits of sharp curves, steep grades, bad drainage, unknown foundation and rough surface; 4.3 km long, and contains obstructions. The road is subject to snow blockage.

c. Measuring Radii oj Curves (fig 14—5) A method of determining the radius of a curve is based on the formula—

Example:

323

324

where: c = length of cord m = perpendicular distance from center of cord to centerline ( <L ) of

road R = radius of circle By fixing m at any convenient distance, such as 2 meters, the formula becomes-

Note. Convert R, c, and m to like units, either feet or meters, before making computations.

In applying the formula, m is measured from the centerline of the curve toward the estimated center of the circle and then c is measured perpendicularly to m making sure that c is centered on m. If c is measured at 16 meters, /? = 17 meters.

d. Determining road gradient. Vertical distance

x 100 = % of slope Horizontal distance

8M 2

Figure 14—5. Measuring the radius oj a curve

14-3. FIXED BRIDGE RECONNAISSANCE

The limiting features of bridges are of basic importance to the selection of a route for normal troop movements. See tables 14—3 and 14—4.

Table 14-3. General Dimension Data Required for Each of the Seven Basic Types of Bridges

NUMBER ON

FIGURE

BASIC TYPE OF BRIDGE

SIMPLE I I I I jSUSPEN STRINGER SLAB T BEAM TRUSS GIRDER ARCH SION

DIMENSIONS DATA

OVERALL LENGTH NUMBER OF SPANS LENGTH OF SPANS

PANEL LENGTH HEIGHT ABOVE STREAMBED

HEIGHT ABOVE ESTIMATED NORMAL WATER LEVEL TRAVELED WAY WIDTH OVERHEAD CLEARANCE HORIZONTAL CLEARANCE

NOTE THE LETTER*’*" INDICATES THE DIMENSION IS REQUIRED

<D ©

til

SIDE VIEW

-©>-

\-—G>

END SECTION

326

Table J 4-4. Capacity Dimension Data Required for Each of The Seven Basic Types of Bridges

CAPACITY ( 1) DIMENSIONS DATA BASIC TYPES OF BRIDGE

SIMPLE STRINGERS SLAB T-BEAMS TRUSS GIRDER ARCH SUSPENSION

THICKNESS OF WEARING SURFACE THICKNESS OF FLOORING, DECK, OR DEPTH OF FILL AT CROWN

DISTANCE, C - TO - C, BETWEEN T-BEAM, STRINGERS, OR FLOOR BEAMS NO. OF T-BEAMS OR STRINGERS DEPTH OF EACH T-BEAM OR STRINGER WIDTH OF EACH T-BEAM OR STRINGER THICKNESS OF WEB OF I-BEAMS,WF- BEAMS, CHANNELS, OR RAILS SAG OF CABLE NO. OF EACH SIZE OF CABLE THICKNESS OF ARCH RING RISE OF ARCH DIAMETER OF EACH SIZE OF CABLE DEPTH OF PLATE GIRDER WIDTH OF FLANGE PLATES THICKNESS OF FLANGE PLATES NO OF FLANGE PLATES DEPTH OF FLANGE ANGLE IWIDTH OF FLANGE ANGLE THICKNESS OF FLANGE ANGLE DEPTH OF WEB PLATE THICKNESS OF WEB PLATE AVERAGE THICKNESS OF FLANGE

REC- TANG

X X

X

(3)

X

CHAN- NEL

X X

X

(3)

X

NOTE: "X" INDICATES REQUIRED DIMENSION. 1. CAPACITY IS COMPUTED BY THE USE OF FORMULAS AND DATA IN BRIDGE MANUALS.

2 DIAMETER. 3 WIDTH OF FLANGE.

a There are two methods of bridge reconnaissance. (1) Hasty reconnaissance used to fulfill immediate requirements. (2) Deliberate reconnaissance when time and personnel are available

to make a thorough analysis and classification of the bridge, including necessary repairs or demolition procedures.

b. Bridge reports include the location of the bridge, bridge number, the military load classification number, length of the bridge, roadway width, vertical clearance, bypasses, horizontal clearance, underbridge clearance, number of spans, type of span construction material, and length and condition of spans (fig. 14—6). Information should be obtained to complete the Bridge Reconnaissance Report Form (DA Form 1249) (figures 14—7 and 14 -8). Consult chapter 7 to determine military bridge classification.

c Bridge bypasses are detours, which are classified as easy, difficult, or impossible. Table 14—1 shows the symbols and requirements for each classification.

14- 4. RIVER RECONNAISSANCE

a Engineer plan must include: (1) Tactical requirement.

What must cross: when and where. (2) Resources available.

i.e.. Bridging, men and support equipment. (3) Riverline data—(see b below).

b Eight common factors for reconnaissance. (1) Road nets.

faj At least same class as largest vehicle crossing. (b) Well drained.

(2) Approaches. (a) Straight for 150'. (b) 10 percent maximum grade. (c) Two lane. (d) All weather, well drained.

(3) Abutments on banks. (a) Same class as bridge. (b) Protect from scouring, using local material. <c) 30" to 40" high to adjust for approach ramps.

327

328 Symbolized on Bridge Reconnaissance Report (DA Form 1249) by Number (Type of Construction) and Letter (Material of Construction)

Example: 3 ah » Beam type bridge constructed of reinforced concrete

(I) TRUSS 2 GIRDER.

(4) SLAB (3) BEAM

Pjh (6) ARCH(Open Spandrol) (5) ARCH (Closed Spandrol)

mp v»r

7) SUSPENSION (8) FLOATING, ■■■

& Use 9 for all other type span construction (i e, swing, lift, cantilever, bascule) specify on reconnaissance report by name

Hctorial Usod in Span Coostnicbon Steel or other metal a (1) Spans which are not useable because of damage are Concrete k symbolized by placed after the dimension of span Reinforced Concrete ak length Pre-stressed Concrete kk (2) Spans which are over water are indicated by placing Stone or Brick p the symbol "W" also after the dimension of the span Wood n length

Figure 14-6. Common types of span construction.

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(4) Width. (a) Direct measurement. (b) Stadii and transit. (c) Triangulation—see number 1, figure 14-9. (d) Scaling from map or aerial photo.

(5) Depth. Sounding or expedient methods.

(6) Current (tide variation)—see number 2, figure 14—9. (7) Assembly sites—desire 100'for each 100' of bridge. (8) Obstructions.

(a) Protect from debris using any expedient methods. (b) Protect from floating mines using anti—mine boom.

c. On a reconnaissance, local populus may be helpful but keep in mind the enemy could be present.

d. Other references—TM 5—210.

14-5. TUNNEL RECONNAISSANCE

Because tunnels are sometimes used for storage, maintenance, or other purposes, their limitations must be known. (See Table 4—1 and FM 5—36)

14-6. FORD RECONNAISSANCE

a. The composition of the stream bottom determines its passability. b. Stream Width.

(1) With a compass, determine the azimuth from a point on the near shore close to the water's edge to a point near the water's edge on the far shore of the stream directly opposite. Then another point, either upstream or downstream from the previously marked azimuth. The distance between the two points on the near shore is equal to the distance across the stream (fig. 14-9).

(2) Stretch a string across the stream, then measure the distance on the string. A measuring tape may be used if one long enough is available.

c. Stream Velocity. Stream velocity is calculated by measuring a distance along the riverbank, then determining the time it takes a light object to float this measured distance (fig. 14—9). Velocity is computed as follows:

331

332

. MEASURING STREAM WIDTH, USING A COMPASS.

o\ / •> ✓ x

*>✓ C o /x \ __

1. SELECT PROMINENT OBJECT A (¡.«..tre«) ON FAR BANK.

2. STAND AT POINT B, OPPOSITE A, AND READ AZIMUTH Xo.

3. MOVE UP OR DOWN STREAM TO A POINT C SO THAT AZIMUTH TO A EQUALS X+45® OR X—45°.

4. DISTANCE BC THEN EQUALS GAP A8.

2. DETERMINING STREAM VELOCITY

C A’ DIRECTION OF CURRENT

B'

A B

DISTANCE AB IS MEASURED FLOATING OBJECT IS THROWN INTO STREAM AT C TIME REQUIRED FOR FLOATING OBJECT TO FLOAT DISTANCE A'B’ IS DETERMINED

V(FPS) = AB (FEET)

TIME TO FLOAT

A*B' (SEC)

Figure 14-9. Methods of veasuring stream width and velocity

Measured distance (m or ft) — velocity in meters or feet per second

Time (sec) Swiftness of the current and presence of debris affect passability of a ford. Current is recorded as swift (over 1.5 meters per second), moderate (1 to 1.5 meters per second), r slow (less than 1 meter per second).

d. Ford Reconnaissance Report. This report is made on DA Form 1251, (Ford Reconnaissance Report). If required, worksheets may be used for rapid field work; details are later transferred to DA Form 1251.

e. For detailed information on ford reconnaissance see FM 5- 36. f. General data can be seen in table 14—5.

TYPE OF TRAFFIC

TRUCKS AND TRUCK-DRAWN

ARTILLERY

LIGHT TANK

MEDIUM TANKS7

SHALLOW FORDABLE DEPTH

(METERS)

1(3*")

1.05(42")

MINIMUM WIDTH

(METERS)

1(39")

(SINGLE FILE)

2(70")

(COLUMN OF 2'S)

3.4(12')

4.2(14')

4.2(14')

MAXIMUM DESIRABLE SLOPE

FOR APPROACHES

2:1

2:1

’BASED ON HARD. DRY SURFACE ^ DEPTHS UP TO 4.3 METERS CAN BE NEGOITATED WITH DEEP WATER

FORDING KIT

Table 14-5. TrajJicability of Fords

14- 7. FERRY RECONNAISSANCE

Ferries differ widely in appearance, capacity, propulsion, construction, etc. For information on ferry reconnaissance, see FM 5—36.

14 8. WATER RECONNAISSANCE

a. Source. When troops are in combat there is usually no time to search for the best water. Units must take whatever is available and purify as needed. For quantities of water required see table 16—2. Principal sources are: surface water (streams, lakes, and ponds), springs, wells, rain, snow, and ice.

b. Capacity of Source (Quantity). Determine the volume of streams, wells or springs, and the dimensions and depths of lakes or ponds, with their rate or outflow. The amount of water that passes a point in one minute is determined as follows:

Q = A x V x 6.4 Where:

Q ® Flow in gallons per minute A = Cross- section area of stream in square feet V « Flow in ft/min. 6.4 = (7.5 gal of water per cu ft) x (correction factor of 0.85).

333

334

c. Quality of Water. Check the color, turbidity, odor, taste, and possible pollution. In a pollution check, examine the drainage area, as much as time permits, for human wastes, industrial wastes, dead fish, or poisoning by enemy action.

d Tests. Tests are performed by personnel operating water supply points and by medical service personnel.

e. Accessibility. There should be a road system connecting a water supply with the users. / Proposed Development. Compute the time, labor, and material

necessary to improve the site. g. Data From Local Inhabitants. Local Records, and Soil Surveys. If a

water source is to be used for some time, information must be obtained on seasonal variations and rdditional sources.

h Standard Symbols The above data should be reported on maps using military symbols and signs described in table 14—1, figures 14- 12 thru 14-16, and FM 21-30.

14-9. ENGINEER RECONNAISSANCE

An engineer reconnaissance is often performed along with a route, or other, reconnaissance. Its primary purpose is to locate engineer materials and to collect and report information on any other factors which might affect engineer operations. The results are usually reported on an overlay similar to the route reconnaissance overlay (fig. 14-1). An Engineer Reconnaissance Report (DA Form 1711-R, figs. 14 -10 and 14-11) is prepared with the map overlay.

a. Front Side. Shows sketch, key number, time, and location of item reported.

b. Reverse Side Gives work estimate of manpower, equipment, and materials to replace, repair, or demolish items reported on the front side of the form. Each work estimate is keyed by number to the appropriate object on the front side of the form. Only those columns which are applicable need be completed. Additional sketches may be drawn if needed.

c. Engineer Reconnaissance Report. Items which should be recorded on the Engineer Reconnaissance Report (DA Form 1711-R).

ENGINEER RECONNAISSANCE RETORT

'CO, 21^1: NCR BN, Aria: S2

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PLACE - HOUR - DATE UT586/08

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CRANES (OPERATIONAL) CHECKED FOB BOOBY TRAPS - NONE

Wo (VT 761432 EXISTING WATER PURIFICATION PLANT

SUPPLYING IIVATER TO TWe CITY ÖF Kucu OUTPUT: 50,000 GAL PER PAY.

'ENGINEER WORK ESTIMATES ON OTHER SIDE

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335

336

ENGINEER WORK ESTIMAYE LOCATION

KEY DESCRIPTION OF WORK UNIT REQ'D

HOURS EQUIPMENT

TYPE NO. HOURS

MATERIALS

TYPE UNIT QUANTITY

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Figure 14-11. Engineer work estimate (back of engineer reconnaissance report).

( 1 ) Where a is. (2) What it is

(u) Obstacles. (b) Engineer materials on site. (c) Engineer equipment required (d) Bivouac areas. Access roads, soil, drainage, size, cover,

concealment, fields of fire. (e) Utilities (J) Water points. (g) Map errors (h) Werk estimates for construction, repair, or removal of any item

encountered on a reconnaissance. (3) Time observed

14-10. RECONNAISSANCE OVERLAY SYMBOLS

a. For frequently used symbols on overlays refer to table 14—1. b. Bridge Symbols. See figure 14-2 for correct bridge reconnaissance

symbols. Consult table 14-2 and chapter 7 for bridge classification procedures.

c Engineer Resource Symbols Use the symbols shown in table 14-1 to depict engineer resources. Possible resources are denoted by dashed line symbols.

d. Airjield Symbols. See FM 21—30. e. Minefield Symbols. See chapter 3.

14-11. UNIT DESIGNATIONS

Far a complete coverage of military symbols see FM 21-30. a. Brunch and Duty Symbols Two or more symbols may be combined.

For example, armored infantry would combine the symbols for armor and infantry. Some of the more common symbols are shown in figure 14-12.

b. Size and Type oj Activity Symbols (Jig. 14-13)

337

338

AIRBORNE

ANTIAIRCRAFT ARTILLERY

ARMOR

ARMY AVIATION

ARTILLERY

CAVALRY

ENGINEER

E3 El S s 1ZI (m)

Figure 14—12. Branch and duty symbols.

TRANSFORT ATION

INFANTRY

MEDICAL

MILITARY POLICE

ORDNANCE

OUARTERM ASTER

SIGNAL

SQUAD

SECTION • •

PLATOON—DETACHMENT a s •

COMPANY— i TROOP—BATTERY BATTALION—SQUADRON I I

ARMY

ARMY GROUP

UNIT REGIMENT—GROUP

BRIGADE

DIVISION

CORPS

I I I

X

XX

xxx

UNIT HQ

ffl

on [1] E3 FÑ1

XXXV

xxxxx

□ p A OBSERVATION

OR LISTENING POST

LOGISTICAL UNIT O

COMBAT SERVICE T~~7

SUPPORT L_^

Figure 14-13. Size and type of activity symbols.

c. Unit Designation and Basic Symbol. The arrangement of various combinations of symbols to depict specific units is shown in figure 14—14. Examples of unit designations and basic symbols for engineer units and weapons are found in figures 14- 15 and 14-16.

SIZE OP UNIT

SU»-

SU»- SUB UNIT/

'SUB-

SUB UNIT / SUB

UNIT

BKANCH OK

DUTT PEKPORMED

PARENT / HIOHER UNIT / ECHELONS

/OF COMMAND

ADDITIONAL INFORMATION

Figure 14—Í4. Unit Designations and Basic Symbols.

7B

— i I

cn> I6TH ARMORED ENGR. BN. 4TH ARMORED DIV.

WLB

, — , AVIB PIATOON, BRIDGE CO.,

3IST ARMORED ENGR. BN.

/ Q z/a/Mz/y «

1ST SO D., 2D HATOON, CO. B., I62D ENGR. BN., STH INFANTRY DIV (MECHANIZED)

SB/ OS rm 4TT

S8IST ENGR. MAINT CO. (DIRECT SUPPORT) attached to 91it Engr. Bn.

Figure 14-15. Exemples of specific engineer unit symbols.

339

340

AUTOMATIC INFANTRY

WEAPON

AIR DEFENSE

MACHINE GUN

ARTILLERY GUN

RECOILESS RIFLE

MISSILE OR ROCKET

Î

1 Hi

I

R

MORTAR

ANTI-TANK ROCKET

LAUNCHER

HOWITZER

ROCKET LAUNCHER

AIR DEFENSE ROCKET

Í

Î

Í

I

0 ARC FULL-TRACKED

ARMORED ASSAULT GUN

APPROXIMATE SIZE OF WEAPON IS AS SHOWN BELOW:

LIGHT, BASIC WEAPON SYMBOL EXAMPLE f

MEDIUM, ONE HORIZONTAL BAR EXAMPLE ?

HEAVY, TWO HORIZONTAL BARS EXAMPLE f

TANK LIGHT MEDIUM

t=rn HEAVY

Figure 14- 16. Weapons symbols

d. Unknown Symbols. When the correct symbol is not known, a symbol may be made up, provided it is explained is a legend added to the map or overlay being drawn.

CHAPTER 15

COMMUNICATIONS

15-1. COMMUNICATIONS EQUIPMENT

See tables 15—1 and 15-2.

15-2. EXPEDIENT ANTENNAS

a. Figures 15—1 thru 15- 4 show expedient antennas using commo wire. These may be used with AM or FM radios to extend their range.

b. In order to determine antenna length in feet, the following formula is used: ~~

Where: F = Frequency in megahertz

15-3. RADIO LOCATION

a. Locate radio as high as possible. b. Location should be away from any metal obstructions. c. Avoid placing in a depression or valley, whenever possjble. d. Avoid locating a radio near electrical power line.

15-4. SECURITY

a. Communication Security (COMSEC). (1) Transmission by radiotelephone should be as short and concise as

possible consistent with clearness. All personnel must be cautioned that transmissions by radio are subject to enemy intercept and, therefore, are not secure.

% wave = ~ 468

Full wave = —

341

342

Table 15-1. Engineer Communications Equipment Reference Guide- Tactical Radio Sets

NOMENCLATURE

TACTICAL RADIO SETS

ANTENNA POWER REQUIREMENT REMARKS

AN/PRC-25 SERIES 30-76 95 MAN-PACK OR VEHICULAR OR BOTH

3' WHIP (FLEX) 10' WHIP AS-1729

BA-386 BA-4386 VEH BTRY

LOW POWER FM. DETENT TUNING. REMOTE/RETRANS CAPABILITIES. 2 PRESETS BEING REPLACED BY AN/PRC-77 SERIES REFERENCES TM 11-6820-396-12. TM 11-6820-

NOTE: AN/PRC-25 SERIES INCLUDES AN/VRC S3 (VEHICULAR) AND AN/GRC-12S (VEHICULAR AND 498-12

MAN PACK) AND AN/PRC-25 (MAN-PACK)

AN/PRC-77 SERIES 30-75 95 MAN-PACK OR VEHICULAR OR BOTH

3'WHIP (FLEX) BA 386 10'WHIP ' 8A4386 AS-1729 VEH BTRY

LOW POWER FM, DETENT TUNING. REMOTE/RETRANS CAPABILITIES. 2 PRESETS. CRYPTO CAPABILITY '(3) REFERENCES TM 1 V5820-667-12. TM 11-6820-498-12

NOTE AN/PRC-77 SERIES INCLUDES AN/VRC-6¿ (VEHICULAR) AND AN/GRC-160(VEHICULAR AND

MAN PACK) AND AN/PRC (MAN-PACK)

AN/VRC-46

AN/GRC 106

AN/GRC 142

2 0 29 999

VEHICULAR MTD. RECEIVER/

TRANSMITTER (RT-S24)

VEHICULAR MTD. RECEIVER/

TRANSMITTER (RT-524) AND AUX RCVR IR-442)

VEHICULAR MTD. AM/SSB RCVR/ TRANSMITTER

VEHICULAR MTD. AM/SSB RCVR/ TRANSMITTER RADIO-TELETYPE SET

10'CENTER- 24V DC (VEH MEDIUM POWER FM. DETENTTUNING FED WHIP BTRYI'd) REMOTE/RETRANS CAPABILITES

CRYPTO CAPABILITY '(3) REFER- ENCE TM 11-6820-401-12

RT-624 24V DC (VEH MEDIUM POWER FM. DETENT TUNING 10'CENTER- BTRY)'ll) REMOTE/RETRANS CAPABILITIES. FED WHIP CRYPTO CAPABILITY *|3) R-442 REFERENCES TM 11-5020-401-12 OR 6' WHIP

IS' WHIP OR VEHICU NO CALIBRATION. NO PRESETS. HAS DOUBLET LAR-100 REMOTE CAPABILITY. REFERENCE

AMP KIT *(2) TM 11-5820-520-12

15' WHIP OR VEHICU NO CALIBRATION. NO PRESETS, HAS DOUBLET LAR-100 FULL SECURE CAPABILITY REFER-

AMP KIT ENCE TM 11.5820-334-12

‘(1) 1 EACH GENERATOR SET. I S KW DC FOR OPERATION IN A STATIC POSITION WHEN AC IS AVAILABLE A PP 2963/U(AC/DC

CONVERTER) IS REQUIRED.

M2) WHEN USED IN A STATIC OPERATION A 1 5 KW DC GENERATOR SHOULD BE USED WHEN AC IS AVAILABLE A PU 620 (AC/DC CONVERTER) IS REQUIRED A TSEC/KW-7 CAN BE USED FOR TELETYPEWRITER MESSAGE SECURITY

M3) COMMUNICATIONS SECURITY CAPABILITY PROVIDED BY ADDITION OF APPROPRIATE COMSEC EQUIPMENT

Table 15—2. Engineer Communications Equipment Reference Guide— Auxiliary Equipment

AUXILIARY EQUIPMENT

NOMENCLATURE DESCRIPTION RANGE REMARKS

AN/GRA—39 REMOTING SET, USED WITH FM RADIO SETS

UP TO 2MI INCREASES FLEXIBILITY OF RADIO SETS. INCREASES SECURITY-RADIO AND ( 3.2 KM) ANTENNA CAN BE EXPOSED WHILE OPERATOR IS NOT.

REFERENCE TM II —$620—477—12

USED TO EXTEND THE RANGE OF TACTICAL FM RADIO SETS. INCREASES RANGE OF RADIO SETS TO APPROXIMATELY TWICE THE STATED PLANNING RANGE OF THE RADIO SET. RADIATING AND GROUND PLANE ELEMENTS MUST BE OF THE PROPER LENGTH FOR A PARTICULAR OPERATING FRE- QUENCY. REFERENCE TM 11—5620—346—15

AT—984 LONG WIRE, END-FED USED WITH TACTICAL FM RADIO SETS. GOOD FOR REDUCING THE ENEMY'S DIRECTIONAL ANTENNA ABILITY TO CONDUCT INTERCEPTION AND JAMMING. CAN EXTEND THE

PLANNING RANGE OF RADIO SETS BY DOUBLE OR MORE. DEPENDING UPON THE ANTENNA USED TO RECEIVE/TRANSMIT AT THE DISTANT SITE.

REFERENCE TM 11—5620—398—12

WIRE EQUIPMENT

GENERAL PURPOSE STATIONARY GROUND PLANE ANTENNA

TA—1/PT SOUND-POWERED 16 KM TELEPHONE IN HAND- SET FORM

TA-312/PT TACTICAL FIELO 35 XM TELEPHONE

LIGHTWEIGHT. MANUAL (MONOCORD) SWITCH- BOARD. LOCAL BATTERY (LB) OPERATION.

SB-993/GT LIGHT, PORTABLE, EMERGENCY SWITCHBOARD

PLANNING RANGE DEPENDS UPON CONDITION OF WIRE (WD-1'TT) NO BATTERIES ARE REQUIRED. INCOMING SIGNAL IS VISUAL AND ADJUSTABLE AUDIBLE. TELEPHONE WIEGHS 2 3/4 LBS, CASE 7/8 LB. REFERENCE TM 11—5605—243—12

PLANNING RANGE DEPENDS UPON CONDITION OF WIRE {WD-KTT) BATTERIES ARE REQUIRED WHEN OPERATION IS IN LB POSITION, AS IN LOCAL CIRCUIT TO SB- 22/PT. INCOMING SIGNAL IS ADJUSTABLE AUDIBLE. HAS HANOFREE OPERATION CAPABILITY. TELEPHONE WEIGHS APPROXI- MATE Y_9!5LBS. REFERENCE TM 11—5605—201—12

SWITCHBOARD HAS 12-CIRCUIT CAPABILITY, AND MAY BE EXPANDED BY "STACKING" ADDITIONAL SB-22S. EACH ADDED SB-22 INCREASES CAPA- BILITY BY 17 CIRCUITS, SINCE ONLY ONE OPERATOR'S PACK IS NECESSARY SIGNALING MAY BE AUDIBLE AND VISUAL, OR JUST VISUAL. REFERENCE TM 11—5605—262—12

SWITCHBOARD HAS 6-CIRCUIT CAPABILITY FOR LOCAL BATTERY (LB) TELEPHONE LINES, WITH AN ADDITIONAL "CIRCUIT PLUG" FOR THE OPERATOR'S USE. INCOMING SIGNAL IS VISUAL ONLY. REFERENCE TM 11—5605—294—15

343

344

AUXlilAIV ANTCNNA

WltC MUST CONNCCT

TO VIHVICAl IIIMINT

T I Aft

VINTICAl tltMCNT

_L OROUNO PLANC

eilMtNTS

49* ANOll

OUV Wilts

AUX ANT

ITAKIS

Figure 15-1. Jungle expedient antenna. (FM)

VERTICAL, POLARIZATION 20 TO 00 MC

FIELD WIRE 3Vt TO 4’/> METERS

ABOVE GROUND INSULATOR

i DIRECTION OF DESIRED

TRANSMISSION

600 RESISTOR II WATT}

RADIO r SET

Figure 15—2. Long wire antenna. (FM)

INSUIATO« INSULATOR

V ANTENNA

WIRE ANTENNA WIRE ✓

✓

.9'oTl- DIO -J V-Mlr J :.

GROUND ROUND STAKES STAKES

Figure 15—3. Expedient suspended vertical antennas. (FM)

y INSULATORS

Yé<+-Yé WAVE \ WAVE

LENGTH X LENGTH

TRANSMISSION LINE

RADIO SET

Eieure 15-4. Improvised center fed half-wave antenna. (AM)

345

346

(2) Security checklist for radio operations. (a) Is radio silence being violated? (b) In unofficial conversation (chatter) being exchanged between

operators? (c) Are transmissions taking place in a directed net, without

permission? (d) Is the operator's personal sign being transmitted? (e) Are call—signs being compromised by their association with

plain language unit designations? (]) Is plain language used instead of authorized pro—signs and

operating signals? (g) Are the operators using unauthorized and incorrect procedures? (h) Do unnecessary transmission occur? (i) Are calls being transmitted excessively? (¡) Is the identification of units and individuals being disclosed in

transmissions? (k) Are transmitting operators sending too fast for receiving

operators? (l) Is excessive transmitting power being used? (m) Are transmitters being tuned with the antenna connected? (n) Is excessive time consumed in tuning, testing changing

frequency, and adjusting equipment? (o) Are authentication requirements and procedures being

violated? (p) Are call—signs and frequencies changed often? (q) Are plain language message cancellations being authenticated? <r) Are service messages concerning cryptographic operations

always encrypted for transmission? (s) Do radio—telephone stations with ciphonv capabilities follow

the procedures in U.S. Supplement 3?

b. Electronic Countercounter-measures (ECCM) ( 1 ) Authenticate tramsmissions as prescribed by local instructions. (2) Learn to readjust the set to minimize effects of enemy jamming. (3) Operate with minimum power commensurate with satisfactory

communication until jammed; then, increase power if necessary to maintain communication.

(4) Change to alternate frequencies and call signs as directed. (5) Observe radio and net discipline at all times. (6) .Stay calm and keep operating when the circuit is jammed.

16- 5. STANDARD RADIO TRANSMISSION FORMAT

CALL MESSAGE (This pro-word indicates message requires recording) PRECEDENCE (Indicates Priority of Call) TIME (Followed by Date—Time Group) FROM (Followed by Call Sign) TO (Followed by Call Sign of Addressee) BREAK TEXT (May consists of plain language, code or cipher groups) BREAK ENDING (Must include either one of two terminating pro—words: OVER or OUT, but never both in the same transmission) EXAMPLE: ZULU FOUR CHARLIE ONE SIX - THIS IS DELTA THREE X RAY TWO NINE - MESSAGE - PRIORITY - TIME 181345Z - BREAK - FIGURES 6 STRINGERS NEEDED AT MY LOCATION ASAP - BREAK - OVER.

347

CHAPTER 16

MISCELLANEOUS FIELD DATA

16-1. WEIGHTS AND SPECIFIC GRAVITIES

Table 16—1 gives weights and specific gravities of materials commonly used in an engineer unit.

16-2. WATER, DISINFECTION AND QUANTITY REQUIREMENTS

a Water Disinfection. (1) Calcium hypochlorite The following procedure is used to purify

water in a one-quart canteen with calcium hypochlorite ampules: (a) Fill the canteen with the cleanest, clearest water available,

leaving an air space of an inch or more below the neck of the canteen. (b) Fill a canteen cup half full of water and add the calcium

hypochlorite from one ampule. Stir until dissolved. (c) Fill the cap of a plastic canteen half full of the solution in the

cup and add it to the water in the canteen. Then place the cap on the canteen and shake it thoroughly.

(d) Loosen the cap slightly and invert the canteen, letting the treated water leak onto the threads around the neck of the canteen.

(e) Tighten the cap on the canteen and wait at least 30 minutes before using the water for any purpose.

(2) Iodine tablets. Use 1 tablet per one quart canteen for clear water and 2 tablets per one quart canteen for cloudy water. Allow the water to stand for 5 minutes, shake well, allowing spill over to rinse canteen neck, and allow to stand another 20 minutes before using for any purpose.

(3) Boiling. Bring the water to a rolling boil for 15 seconds.

Table ¡6 -1. Weights and Specific Gravities

Substance

Weight lbs. per cu. ft.

Specific gravity

Asphaltum Petroleum, gasoline, & diesel Tar, bituminous Cement, Portland, loose Cement, portland, set Clay, damp, plastic Clay, dry Earth, dry, loose Earth, dry, packed Earth, moist, loose Earth, moist, packed Sand gravel, dry. loose Sand gravel, dry, packed Sand gravel, wet Water, 4° C. (max density) Water, ice Masonry, ashlar

Granite, syenite, gneiss Limestone, marble Sandstone, bluestone

Masonry, brick Pressed brick Common brick Soft brick

Masonry, concrete Cement, stone, sand

Masonry, dry rubble Granite, syenite, gneiss Limestone, marble Sandstone, bluestone

Masonry, mortar, rubble Granite, syenite, gneiss Limestone, marble Sandstone, bluestone

81 42 75 94

183 110 63 76 96 78 96

90-105 100-120 118 120

62.428 56

165 160 140

140 120 100

144

130 125 110

155 150 130

1.1-1 5 0.‘66-0.69 1.20

2 7-3 2

1.0 0.88-0.92

2.3-3 0 2.3 2 8 2.1- 2.4

2.2 2.3 1.8-2 0 1.5 1 7

2.2- 24

1.9- 2.3 1.9- 2 1 1.8-1.9

2.2- 2.8 2.2 2.6 2.02.2

349

350

Table 16—1. Weights and Specific Gravities (Con't)

Substance Weight

lbs. per cu. ft. Specific gravity

Aluminum, cast, hammered Copper, cast rolled Iron, cast, pig Lead Magnesium alloys Steel, rolled Limestone, marble Sandstone, bluestone Riprap, limestone Riprap, sandstone Riprap, shale Glass, common Hay and straw (bales) Paper Stone, quarried, piles

Basalt, granite, gneiss Greenstone, hornblende Limestone, marble, quartz Sandstone Shale

Excavations in water Clay River mud Sand or gravel Sand or gravel and clay Soil or gravel and clay Stone riprap

Timber, US, seasoned (moisture content by weight: 15-50%) Soft wood Medium wood Hard wood

165 556 450 710 112 490 165 147

80-85 90

105 156 20 58

96 107 90 82 92

80 90 60 65 70 65

25 40 55

2.55-2.75 8.8-9.0 7.2 11.37 1.74-1.83 7.85 2.5-28 2.2-2.5

2.4-2.6

0.70-1.15

.40

.63

.87

(4) Destruction of amoebic dysentery cysts. When cysts are suspected, pretreat all water by coagulation and sedimentation followed by sand filtration at reduced rates or by diatomite filtration. Water treated in this way is safe to drink if it has a residual chlorine content of 1 ppm after a 10-minute contact time. In emergencies, disinfect water in individual canteens by following the directions on the bottle of individual water purification tablets unless an increase is directed by the medical officer. Small units may boil their drinking water; this is a sure method. If the lyster bag is used, the following steps must be taken:

(a) Break 1 ampule of calcium hypochlorite and pour into filled bag. Stir with clean paddle.

(b) Disinfect faucets by flushing % cup of water through each faucet.

(c) After 10 minutes, residual should exceed 1 ppm. Then add another ampule. Keep bag covered.

(d) Water is potable 30 minutes after adding last ampule. b. Daily Water Requirements. Table 16—2 gives water requirements in

gallons per unit consumer per day under various conditions of use.

16-3. ELECTRICAL WIRING

a. The procedures pointed out in this section are to be used only for an estimation of required wire sizes or when no other method is known.

b. To determine the wire size required for a given load: (1) Convert load into amperes required by using

(2) Enter table 16—3 or 16—4 with amperes to be serviced and length of wire required. Determine wire size needed.

(3) This procedure is to be used when power is to be furnished to a specific load such as one motor or a group of lights. The procedure for wiring a facility or wiring a generator is shown in FM 5—35 and TM 5—766.

Amperes =

Amperes = Total watts to be serviced

voltage Voltage

Amperes =

resistance (ohms) 745.7 x Horsepower

voltage

351

35

2

Table 16-2 Daily Water Requirements

Unit Consumer Conditions of Use

Gallons/Dey

Mild/CoM Desert/Jungle Remaries

Man

Vehicle

Hospital

In Combat: Minimum

Normal

March Temporary camp

Temporary camp

Semi-permanent camp Permanent camp

Level and rolling Mountainous Drinking and cooking Water waterborne sewerage

%-1 2 3

2 S

15

30-60 60-100 V.-Î4 ’/«-I

10/bed 50/bed

2- 3 3- 4 62

Eating and drink (3 days) When field rations used. Drinking plus cooking and personal hygiene. Minimum for all purposes. All purposes (does not include bathing). Waterborne sewage system and bathing.

Does not include bathing Includes medical personnel.

' For unacclimatized personnel or for all personnel when dry bulb readings exceed 105°F, in the jungle. J ‘Maximum consumption factor is dependent upon work performed, solar radiation and other environmental stresses.

Table ¡6—3. Wire SizesJor 1 ¡O—Volt Single-Phase Circuits

10-ALUMINUM WIRE 12-COPPER WIRE

FOR 110V CIRCUIT DISTANCE TO LOAD IN FEET LOAD

IN AMPfl.

15

20

25

30

40

50

60

70

80

90

100

50

10 12

10 ir

?” nr

10

6 T

“T" 8

4 T 4 T

_4_ 6

"T" 4

£ 4

75

± 10

8 nr

6 T

“T" 8

4 T

2_ 4 __

4

~£ 4

l_ 3

J_ 8

100

10

6 T

6 T

A 6

4 T

_3_ 4

"T" 4

JL 3

_1_ 3

x 2

0_ t

125

"T

?”

T

_4 6

4_ 6

4

_2_ 4

_1_ 3

5" T

_0 2

2/0 1

2/0 1

150

e T

4 T

4 T

j. 4

£ 4

J_ 3

"o_ 2

2/0 2

2/0 l

3/0 1

3/0 0

200 4 T

4~

_3_ 4

4

_1_ 3

_0^ 2

2/0 1

3/0 0

3/0 0

2/0

Izó" 2/0

250

4 T r T

“2” 4

3

£ 2

2/0 1

3/0 0

4/0 575

"¡¿<r 2/0

250 3/0

300 8/0

300

r T

2 4

J_ 3

_0 2

2/0 1

3/0 0

4/0 ITS

250 “STS’

260 3/0

300 3/0

360 4/0

400

~ T J_ 3

2

2/0 1

3/0 0

4/0 STS’

~260 37S

300 47^

360 4/0

400 250

500 250

500 1 T

£ 2

2,/Q 1

3/0 0

4/0 2/0

300 37ÏÏ

350 477

400

500 250

500 300

600 350

353

354

Table 16-4. Wire Sizes for 220- Volt Three-Phase Circuits

10—ALUMINUM WIRE 12—COPPER WIRE

FOR 220V CIRCUIT DISTANCE TO LOAD IN FEET LOAD

IN AMPS.

15

20

25

30

40

50

60

70

80

90

100

100 Ü 12

10 12

JL 10

_6 10

8

_4_

8

6

6

6

2_

4

2_ 4

200 jl 10

_6 8

±_ 8

4 6

± 6

3_

4

2_

4

JL 3

3

£

2

J). 2

300 £

8

_4 6

_4. 6

_3_

4

2^ 4

J_

3

0 2

2/0 2

2/0 1

3/0 0

3/0 0

400 ± 6

6

4

_2_

4

1 3

0 2

2/0 1

3/0 0

3/0 0

4>0 2,0

4/0 2/0

500

6

_3 4

2_ 4

_1_

3

0 2

2/0 1

3/0 0

l/T 2/0

4/0 2/0

250 3/0

300 3/0

600 _3 4

_2 4

J_

3

_0 2

2/0 1

3/0 0

4/0 2/0

250 2/0

250 3/0

300 4/0

350 4/0

700 _2 4

_1 3

0 2

2/0 2

3/0 0

4/0 2/0

250 2/0

300 3/0

300 4/0

350 4/0

400 250

800 _2

4

1_

3

£

2

~i/<r 1

3/0 0

4/0 2/0

250 3/0

300 T/Ô 360 4/0

400 250

500 250

900 £

3

0 7

2/0 1

3.0 0

4/0 2/0

250 3/0

300 4/0

350 4/0

400 250

500 300

500 300

[1000 _1 3

0

T

2/0 1

3/0 0

4/0 S73

300 3/0

"sso 4/0

400 250

500 253 500 300

600 359

16-4. TIMBER

a. Board Measure, Size and Weight. (1) Lumber quantities are expressed in feet, board measure (ft.b.m.)

or in board feet (bd.ft.), or in thousand board feet (M bd.ft.). One board foot is the amount of lumber in a rough-sawed board 1 foot long, 1 foot wide, and 1 inch thick (144 cubic inches) or the equivalent volume in any other shape. The originals or "nominal" dimensions and volumes determine the number of board feet in a given quantity of dressed lumber, regardless of the fact that the process of surfacing or other machining has reduced the actual dimensions and volume. Under American standards, for example, a dressed board designated as 1 inch by 12 inches is in fact 25/32 inch by 11% inches. This must be taken into account in computing the amount of lumber needed for a given job. Thus, one hundred 1-inch by 12-inch dressed boards

16 feet long contain 100 x 1 x 12 x 16

12 -= 1,600 board feet, but have an

100 x 11% x 16 actual area of only — = 1,533 square feet; so that if 1,600

square feet of 1-inch by 12-inch material are desired, 1,670 board feet, plus allowance for wastage, must be ordered.

(2) Table 16—5 gives the number of board feet in one piece of lumber for the common sizes given. For other sizes use multiples of values given (i.e. for a 2 x 8 use the value for the 2x4 doubled).

(3) Table 16—6 gives nominal size, dressed size, section area, and weight per foot of the most common sizes of southern pine timbers.

b. International Log Rule. The board measure of volume of a log can be estimated by measuring the diameter at the small end (do not include the bark) and using table 16-7.

16-5. NAILS AND FASTENERS

a. Nails and Spikes. The safe lateral load for one nail or spike driven into the side grain of seasoned lumber (so that at least two-thirds of the length of the nail is in the wood member holding the point) Is as follows (reduce load 60 percent for nails in end grain and 25 percent for unseasoned wood):

355

356

Table ¡6-5. Board Feet

Size of piece (inches)

2 by 4

2 by 6

2 by 10

2 by 14

3 by 6

3 by 8

3 by 10

3 by 14

4 by 4

4 by 6

4 by 10

4 by 14

6 by 6

6 by 8

6 by 10

6 by 14

6 by 18

8 by 8

8 by 10

8 by 12

8 by 14

Length of piece (feet)

10

6Vj

10

16V]

23'A

15

20

25

35

13 V]

20

33‘A

46Vi

30

40

50

70

90

53'A

66 Vj

80

13V,

8

12

20 28

18

24

30

42

16

24

40

56

36

48

60

84

108

64

80

96

112

14

9%

14

23'A

32V]

21

28

35

49

18V,

28

46V]

65V,

42

56

70

98

126

74V,

93'A

112

130V,

16

10V,

16

26V,

37V,

24

32

40

56

21V, 32

53'A

74V,

48

64

80

112

144

85 V,

106 V,

128

149V,

18

12

18

30

42

27

36

45

63

24

36

60

84

54

72

90

126

162

96

120

144

168

20

13 V,

20

33 V,

46V,

30

40

50

70

26V,

40

66V,

93'A

60

80

100

140

180

106 V,

133 V,

160

186V,

22

14V,

22

36V,

51'A

33

44

55

77

29%

44

73%

102 V,

66 88

110

154

198

117%

146 V,

176

205%

24

16

24

40

56

36

48

60

84

32

48

80

112

72

96

120

168

216

128

160

192

224

NOTE For other dimensions use multiples of above values, (i.e., for 12 x 10 use the value of a (6 x 10) x 2)

Tuhic I fi- fi ft(j/>eritcs <ij Souillent Pine Beams

NOMINAL SIZE

ACTUAL SIZE DRESSED

S S

AREA OF SECTION BD.

A. SO. INS.

WEIGHT PER FOOT (POUNDS)

2 4 2 6 2 4 6 8 2 6

10 2 3 6 8

10 2 3 6

10 14 2 3 8

12 14 16 4 8

12

4 4 6 6 8 8 8 8 10 10 10 12 12 12 12 12 14 14 14 14 14 16 16 16 16 16 16 18 18 18

5/8 5/8 5/8 5/8 5/8 5/8 5/8 1/2

1 5/8 5 5/8 9 1/2 1 5/8 2 5/8

5/8 1/2 1/2 5/8 5/8 5/8 1/2

13 1/2 1 5/8 2 5/8 7 1/2

11 1/2 13 1/2 15 1/2 3 5/8 7 1/2

11 1/2

3 5/8 3 5/8 5 5/8

5/8 1/2 1/2 1/2 1/2 1/2 1/2 1/2

11 1/2 11 1/2 11 1/2 11 1/2 11 1/2 13 1/2 13 1/2 13 1/2 13 1/2 13 1/2 15 1/2 15 1/2 15 1/2 15 1/2 15 1/2 15 1/2 17 1/2 17 1/2 17 1/2

5.89 13.14 9.14

31.64 12.19 27.19 42.19 56.25 15.44 53.44 90.25 18.69 30.19 64.69 86.25

109.25 21.94 35.44 75.94

128.25 182.25 25.19 40.69

116.25 178.25 209.25 240.25 63.44

131.25 201.25

1.63 3.64 2.53 8.76 3.38 7.55

11.72 15.58 4.28

14.84 25.00 5.18 8.39

17.96 23.89 30.26 6.09 9.84

21.09 35.53 50.48 7.00

11.30 32.20 49.37 57.96 66.55 17.62 36.36 55.75

•IN SOME SPECIES 5 1/2"IS THE DRESSED SIZE FOR NOMINAL 6" X 6" AND LARGER.

357

358

Table 16-7 Log Scale ( Board Measure of Volume)

Length of log in feet (board measure)

Diameter (Inches) 8 10 12 14 16 18 20

6

8

10

12

14

16

18

20

24

28

32

36

40

44

48

10

15

30

45

65

85

110

135

205

280

375

475

595

725

865

10

20

35

55

80

110

140

175

255

355

470

600

750

910

1090

15

25

45

70

100

130

170

210

310

430

570

725

900

1095

1310

15

35

55

85

115

155

200

250

370

S'O

670

855

1060

1290

1540

20

40

65

95

135

180

230

290

425

585

770

980

1220

1480

1770

25

45

75

110

155

205

265

330

485

665

875

1115

1380

1675

2000

25

50

85

110

175

235

300

370

545

745

980

1245

1540

1870

2235

900 x for white pine and eastern hemlock 1200 x for Douglas fir and southern yellow pine 1700 x 0^/2 for oa|Ct asht and hard maple

Where D = diameter of nails, in inches. See table 16—8.

b. Wood Screws The safe lateral load, in pounds, for one wood screw, driven into the side grain of seasoned lumber to a penetration of at least seven times the diameter into the member receiving the point, is as follows (reduce load 25 percent for end grain and 25 percent for unseasoned wood):

2100 x for white pine and eastern hemlock 2700 x for Douglas fir and southern yellow pine 4000 x D^ for oak, and hard maple

See table 16- 9.

Table J 6—8. Nail and Spike Sizes

SIZE LENGTH, IN

COMMON

DIAMETER (D)

GAGE NO./LB INCHES D3/2

FINISHING

GAGE NO./LB

FLOORING

GAGE NO./LB 3D

4D 6D 8D 10D 12D 16D 20D 30D 40D 60D

1/4 1/2

1/2

1/4 1/2

1/2

14 12 1/2 11 1/2 10 1/4

9 9 8 6 5 4 2

568 316 181 106 69 63 49 31 24 18 11

.0800

.0985

.1130

.1314

.1483

.1552

.1620

.1920

.2070

.2253

.2625

.0226

.0309

.0380

.0476

.0570

.0611

.0652

.0841

.0942

.1066

.1347

15 1/2 15 13 12 1/2 11 1/2 11 1/2 11 10

807 584 309 189 121 113 90 61

11 10 9 8 7 6

157 99 69 54 43 31

SPIKES 7" 8"

9" 10"

12"

7" 8"

9" 10"

12"

5/16" 3/8" 3/8" 3/8" 3/8"

5/16" 0.1750 3/8" 3/8" 3/8" 3/8"

.2295

.2295

.2295

.2295

NOTE: TO AVOID SPLITTING, NAIL DIAMETERS SHOULD NOT EXCEED ONE-SEVENTH OF THE THICKNESS OF LUMBER TO BE NAILED.

FORMULA TO FIND APPROXIMATE NUMBER OF NAILS REQUIRED. NO. LBS.( 12D TO 60D, FRAMING) = D/6 x BF/100 NO. LBS (2D TO 12D, SHEATHING) = D/4 x BF/100 WHERE D = SIZE OF DESIRED NAIL IN PENNIES

BF = TOTAL BOARD FEET TO BE NAILED

359

360

Table ¡6—9. Wood Screw Diameters

Size Diameter-D Inches

D2

Inches2

'Á inch—No. 4

% inch—No. 8

1 inch—No. 10

11/2 inch-No. 12

2 inch-No. 14

2% inch-No. 16

3 inch-No. 18

0.1105

.1631

.1894

.2158

.2421

.2684

.2947

0.0122

.0266

.0359

.0466

.0586

.0720

.0868

1900 x D2 for southern yellow pine and soft maple 2200 x D2 for oak, ash, and hard maple Where D = diameter of shank, in inches.

c Lag Screws. The safe lateral load, in pounds, for one lag screw, driven into the side grain of seasoned lumber to a penetration of nine times the diameter into the member receiving the point, and holding a cleat having a thickness of 3.5 times the screw diameter, Is as follows (reduce load 35 percent for end grain and 25 percent for unseasoned wood):

1500 x D2 for white pine and eastern hemlock 1700 x D2 for Douglas fir and southern cypress

d. Drijtpins. ( 1 ) Description. "Drlftpins” (or "drlftbolts") are long, heavy,

threadless bolts or bars used to hold heavy pieces of timber together. Drlftpins may or may not have heads and vary In diameter from % to 1 Inch, and in length from 18 to 26 Inches.

(2) Use. To use the drlftpins, a hole slightly smaller than the diameter of the pin Is made in the timber. The pin Is wiped with oil, driven Into the hole, and held In place by the compressive action of the wood fibers.

16-6. CAMOUFLAGE

a Factors of Recognition. When camouflaging activities, personnel, equipment, or installations, the camouflage should try to alter or eliminate the six factors of recognition as much as possible. The six factors are as follows:

(1) Shape (2) Shadow (3) Color (4) Texture (5) Position (6) Movement

b. Principles (1) Siting Careful selection of the position for an emplacement of

equipment is the most important principle of camouflage. Emplacements and their artificial camouflage materials must be made to blend with their background.

(2) Discipline. Avoid unnecessary movement of personnel and vehicles and any other activity that would change the original appearance of the area and indicate your presence to enemy observers.

(3) Construction. Employ natural and artificial construction and camouflage materials to conceal the position.

c. Materials. (1) Natural. Natural materials generally provide the best

concealment and are always available. Natural materials include live vegetation, cut vegetation, debris, soil, and so forth.

(2) Artijicial Material. Artificial materials include paints, supporting frames, garnishing materials,' structural materials, screening materials, adhesives, and texturing materials. See table 6-10 for expedient paints that can be made from materials readily available. FM 5—35 has more detail on camouflage materials and man-hour requirements .involved.

(3) Lightweight Camouflage Screen. The lightweight camouflage screens are issued in two type, radar scattering and radar transparent. The basic issue is by module (screen and supports). Multiple screens can be joined together to provide larger screens (see figs. 16- -1 and 16—2). The camouflage screens are issued in these color type.

361

362

fa) Woodland blend, a reversible spring/summer and fall/winter

screen. (b) Desert blend, a reversible desert grey and desert tan.

(ci Snow blend.

Table 16-10. Expedient Paints

Paint Materials Mixing Color Finish

Local earth, GI soap, water, soot paraffin

Mix soot with paraffin, add to solution of 8 gal water and V> lbs soap. Stir in earth

Dark gray Flat. lusterless

No. 2 Oil, ground clay, water, gasoline, eacth

Mix 2 gal water with 1 gal oil and Vi to V* gal clay, add earth. Thin with gasoline or water

Depends on earth colors available

Glossy on metal; otherwise dull

No. 3 Oil, clay, Gl soap, water, earth

Mix V/i bars Gl soap with 3 gal water, add 1 gal oil; stir in 1 gal clay. Add earth for color

Depends on earth colors

Glossy on metal, dull on other

NOTE Canned milk or powdered eggs can be used to increase binding properties of either issue or field-expedient paints.

ONÊ MODULE

MULTIPLE MODULE SYSTEMS

<§>1iv T T

32 2 40 2 1

h-27 9-H k-27 9'-4 H—

Note: Diamond and hexagon screens may be used spearated or joined.

TWO MODULES THREE MODULES

48 3

H 55 8-

FOUR MODULES 55 8

64 4’

55 8

FIVE MODULES + 1 DIAMOND

80 5

£3 80.5'

L 83 7-

Note: All hexagon and diamond shaped nets are fastened together with quick-release connectors.

Figure 16- 1 Lightweight camoujlage screens.

363

Ü33J) V

364

HASTY

MODULE DETERMINATION CHART A=2h+w+5ft B=2h4L+5ft

190

00

70

00

150

MO

NOTE: NUMBER WITHIN EACH. AREA EQUALS NUMBER

' OF MODULES

130

no -

no

100

30-

———————————————— 10 20 30 40 50 to 70 00 90 100 1)0120130140)50160170 100

B (FEET) NOTE: This chart is normally reliable for vehicles of

regular configuration. Vehicles of irregular configuration such as artillery pieces or cranes may require additional modules.

Figure 16—2 Hasty module determination chart.

d Individual Camouflage. Make use of terrain and background, adapt clothing to the terrain, and select a route during movement that makes use of the concealment available.

( 1 ) Helmets. Break up the shape of helmets by using leaves or twigs secured with a rubber band, making a cover of burlap, distorting with burlap garlands, or painting appropriate colors.

(2) Skin. Tone down all visible skin areas with face paint, burnt cork, lampblack, or charcoal (use a non-shine substance).

(3) Clothing. Clothing may be toned down to blend with the background by the use of camouflage paints, or attaching vegetation to blend in with existing area.

(4) Equipment. Remove shine from metal objects with mud or face paint. Any equipment which may make a noise should be muffled by padding.

e Camoujlage oj Equipment and Emplacements. (1) All military vehicles and equipment have regular geometric

configurations or characteristic shapes and interior shadow. These so-called signatures contrast with natural surroundings^ and make the object conspicuous. To make the item less conspicuous, the identifying characteristics of shape, shadow, and highlights must be disrupted in a manner that makes military vehicles and equipment more difficult to perceive. Natural camouflage material supplemented with artificial materials such as pattern painting with lusterless camouflage paint, contributes significantly toward disrupting the signature characteristics of military vehicles and equipment. Avoid regular geometric layouts of the position of vehicles, weapons, and supplies.

(2) Conceal the tracks made by vehicles so that terrain remains the same.

(3) Eliminate shine on vehicles. (4) Use shadows and insure that the silhouette of emplacements and

equipment is broken so that the general outline is not detectable. (5) In urban areas, use shadows cast by buildings.

f. Garnishing of Camouflage Nets. (1) Garnishing density. Drape nets should be garnished 100 percent

in the center portion of the net, thinning out to 65 percent toward the outer edges. This will result in a coverage of about 85 percent of the entire net area. Flattop nets should be garnished 100 percent in the center portion of

366

the net, thinning out to 25 percent toward the outer edges. This will result in a coverage of about 65 percent of the entire net area. Begin the thin-out at about one-half the radius of the net. This must not be on an abrupt change in percentages, but rather a gradual thinning-out so as to achieve a smooth transition to the desired density at the outer portion of the net.

(2) Garnishing Patterns. To provide for blending into a variety of seasonal and geographic terrain characteristics, pregarnished twine nets are issued in two blends- the all seasonal and the desert. The color blend of a net is achieved by proportionately varying the garlands of the various colors required for a particular blend, and placing the garlands in the net as an overall mixture of colors. Long, straight runs, large areas, blocks of one color, or regularity of pattern in a net should be avoided. Generally, the garlands are inserted into the net in such a manner that each garland will describe one of the following letters. L, U, S, C, or 1 (fig. 16—3). This should result in an amalgamation of the letter pattern forming the desired degree of density and color blend.

5 £ zz 22

L PATTERN U PATTERN S PATTERN

C PATTERN I PATTERN

Figure 16-3. Garnishing.

g Calculation oj Net Size. (1) Drape net.

Length = 2H + L + 5' Width = 2H + W + 5'

(2) Flat top net. Length = 4(H + 2) + L Width = 4(H + 2) + W

Where: L = length of object being camouflaged W = width of object being camouflaged H = height of object being camouflaged

16-7. VEHICLE RECOVERY EXPEDIENTS

a. General. For a complete coverage of all aspects of vehicle recovery see FM 20-22.

b Field Expedient Vehicle Recovery See figures 16—4 thru 16—7.

rJ G3Z> X-

Figure 16—4 Use oj dual wheels J'or a winch

367

36

8

í%i CABLESECUBED ABOUND LOO AND TBACK

'It

Figure 16-5. Log used to provide track traction.

ft 53*.

"Vf. (rfï-'il

Figure 16—6. Simple lever.

4¡°»r Of ''tH

'de

ROTATION

LOO CHAIN

NOT!: LOG ANCHORED TO WHEEL ACTS!

AS LIFT AS WHEEL ROTATES, NO SLIPPAGE

Figure 16— 7. Log used to provide wheel traction.

369

16-8. FLAME FIELD EXPEDIENTS

a. Genera! Flame field expedients are flame devices improvised in the field. They are usually used in the defense but could be employed in offensive operations. They are used for their incendiary, illuminating, and signalling effects.

b. Materials and Equipment Required. See figure 16—8. (1) Fuel ingredients (gasoline and M4 thickener) (2) Wooden mixing/measuring paddle (3) Container (5 to 55 gals) (nongalvanized) (4) Burster to scatter fuel (M4 burster, det cord, or other explosive) (5) Igniter (when M4 burster is not used) (6) Bucket and funnel (to transfer mixed fuel to container)

Caution: Insure no open flames in or near mixing/storage site. Do not put hands in gas. Keep out of eyes and mouth. Never mix inside a tent or building. Have carbon dioxide fire extinguishers available when mixing.

c. Mixing Procedure, (gasoline: 32° to 85° F) (1) Quantity of M4 thickener

Rule of Thumb: ounces of M4 thickener = gals of gasoline x 3 (constant) Example:

M4 = 40 gals of gasoline x 3 M4 =120 ounces tf'/i lbs) (use 3 — 2% lbs cans of M4 thickener)

(2) Add unclotted M4 thickener to gasoline while stirring. (3) Mix till applesauce texture is achieved (5-10 minutes). (4) Allow the fuel to age from 6 to 8 hours. (Can be emplaced while

aging) d. Types of Flame Field Expedients.

(1) Exploding Flame Device, see figure 16—9. (a) area of coverage:

5 gal = 20—30 meters 55 gal = 85 meters

(b) Detonator: 1—M4 burster/5 gal can 2 to 3—M4 bursters/55 gal drum ¡0 to 12 wraps of det cord and a WP grenade for ignition.

MEASURING

ANO MIXING PAOOlE (Wooden)

SS—GALLON OIUM OPEN TOP

(Ungolvoniied)

LAtOEFUNNEL

S-GALLON BUCKET

Figure 16-tj Equipment used in handmixing flame luei.

7

IS - TO S5 - GALLON OIL DRUM OR SIMILAR CONTAINER FILLED WITH THICKENED FUEL

DETONATING CORD- WP HAND GRENADE ASSEMBLY

DETONATING CORD BLASTING CAP3

Figure ¡6-9. ■ Exploding 55 gallon Jlame device.

371

372

(2) Flame Fougasse, a variation of an exploding flame device. The direction of burst is controlled. See figure 16—10.

PISTON OR PUSHER PLATE

METAL CANISTER FOR 8-IN. HOWITZER PROPELLING CHARGE

ELECTRIC BLASTING CAP WIRE BROUGHT OUT THROUGH HOLE

CAUTION: LEADWIRE INSULATION MAY BE DAMAGED BY FUEL.

COVER

IGNITER

DETONATING CORD- WP HAND GRENADE ASSEMBLY WITH BLASTING CAP

THICKENED FUEL

DETONATING CORD. 3-5 CIRCLES. FLATTENED SIDE BY SIDE ENCASED IN PLASTIC BAG ITNT or Claymore can be used)

TO SWITCHBOARD, BLASTING MACHINE, OR BATTERY

Figure 16—10. Flame fougasse (howitzer propelling charge container).

(3) Flame Illuminators. The Husch-type flare (figures 16—11) will illuminate a radius of 50 meters for 4- 5 hours.

(a) Materials for construction. 1 Sealed metal container (powder canister) % full of thickened

fuel (1/8 to 3/16 hole in bottom) 2 Half of a 55 gal drum % full of thickened fuel 3 Reflector (24" culvert half) 4 Igniter (tripflare or WP grenade)

(b) Method of operation. 1 Place the metal container, cap down, into 55 gal half drum of

thickened fuel (bottom with the 1/8 hole up). 2 When the half drum is ignited, the heat from the burning fuel

produces vapor inside the metal container which is expelled asa flaming jet through the hole.

3 The reflector (culvert) should extend about 60 centimeters above the top rim of the drum.

— ENGINEER STAKE

) ^ 1/8 to 3/16 INCH HOLE

./ZS ^ POWDER CANISTER

^PUEL LEVEL

HALF OF 55 GALLON DRUM

Figure 16-11 Husch-type flare

373

374

c Methods oj Firing. (1) May be wired to fire electrically on an individual basis, in groups,

or simultaneous ignition. (2) Can be rigged with trip wires for immediate or delayed firing. NOTE Electric and nonelectric blasting caps can be used with various

burster/igniters. / Emplacement oj Flame Field Expedients. Two basic patterns for

emplacement are shown in figure 16—12.

BECAUSE THERE ARE BUT 51 M TRIPWIRE ISSUED WITH FIVE OF THE FUZES, WHERE 93 M ARE REQUIRED FOR PROPER EMPLACEMENT OF FIVE UNITS, SUBSTITUTE MATERIAL FOR TRIPWIRES MUST BE USED. IT IS SUGGESTED THAT TELEPHONE WIRE BE USED BECAUSE OF ITS DARK COLOR, AVAILABILITY, AND CASUAL APPEARANCE. TELEPHONE WIRE MAY ALSO BE USED AS A LANYARD ATTACHED TO THE TRIPWIRE AND RUN BACK TO A FIRING BUNKER.

Figure 16-12. Nonstandard emplacement patterns Jor 55 gal Jlame Jield

TRIPWIRE

PARALLEL EMPLACEMENT

10 ENEMY FORCES

EXPLODING FLAME DEVICE

FRIENDLY FORCES

TRIANGLE EMPLACEMENT NOTE:

expedients.

16-9. TRIGONOMETRIC FUNCTIONS

a Table 16-11 gives the formulas for solving right and oblique triangles.

b. Table 16—12 gives the natural trigonometric functions.

Table 16-11. Trigonometric Solution oj Triangles

SmB SmC . ,2 _

* bz - ?* Cot C

' RIGHT TRIANGLE

Cot A • b/c

OBLIQUE TRIANGLE

C /.li-c)

a V * ■iz:,

i2 un B w C

375

376

Table 16—12. Natural Trigonometric Functions

2° 3° 4° 6°

6° 7° 8°

9° 10P

IIo

12°

13° t4° 15° 18° 17° 18° 10°

20°

21°

22°

23° 24° 26° 26° 27° 28° 29° 30° 31° 32° 33° 34° 36° 36° 370

38° 39° 40° 41° 42° 43° 44° 46°

Sin

.000

017

.038 062

070

.087

106

122

.139

1G6

174

191

.206

.225

242

259

.278

292

.309

.328

.342

368

375

.391

407

.423

438

454

469

.485

.500

.515

530

.545

.559

.574

688

.802

.818

829

843

866

67 30

28 65 19 11

14 34

11 47

6.687

8 206

7 185

6 392

5 759

6 241

4810

4 445

4 134

3 884

3 628

3 420

3.236

3.072

2 924

2 790

2669

2.659

2.459

2366

2.281

2.203

2 130

2.063

2.000

1 942

1 887

1.838

1.788

1.743

1 701

1.662

1.624

1.689

1 556

1 524

1 494

1 466

1 440

1 414

.000

017

035 052

.070

087

106

.123

.141

168

176

194

213

231

249

268

287

308

325

.344

.384

384

.404

.424

.445

510

532

.564

.677

601

625

649

.676

700

727

754

761

900

933

1 000

Cotan

57 29

28 64 19 08

14 30

11 43

9514

8.144

7.116

6 314

6871

5 146

4 706

4 331

4011

3 732

3 487

3 271

3 078

2904

2 747

2605

2 475

2 356

2 246

2 145

2050

1 963

1 881

1 804

1.732

1 664

1.600

1 540

1 48? 1.428

1 376

1 327

1.280

1.235

1 192

1 ISO

1 111

1.072

1 036

1 000

1 000

1.001 1 001

1.002

1 004

1 006

1.008

1 010

1.012

1 015

1 019

1 022

1 026

1 031

1 035

1 040

1 046

1 051

1.058

1 084

1 071

1 079

1 088

1.095

1.103

1 113

1 122

1 133

1 143

1.165

1.167

1.179

MOT

1.208

1 221

1 236

1 252

1 289

1.287

1.305

1 32S

1 346

1 367

1 390

1 414

Cowc

1.000

1 000

999

995

993

990

982

978

974

.970

966

961

966

951

946

.940

934

.927

921

914

.906

899

875

886

657

848

819

.809

799

788

777

766

755

743

731

719

707

85° 84° 63° 82° 81° 80° 79° 78° 77° 76° 75° 74° 73° 72° 71° 70° 69° 68°

67° 66°

66°

64° 63° 62° 81° 60° 59° 68« 67° 56° 55° 54° 53° 62° 51° 50° 49° 46° 47° 46°

16-10. LENGTHS, AREAS, AND VOLUMES OF GEOMETRIC FIGURES

a. Legend. A = area h = height b = length of base c = hypotenuse C = circumference V = volume r = radius D = diameter n = 3.1416 L = length of arc K = length of cord

b. Formulas.

c Sin ij) or: Sin y

(1) Any triangle: A = 1/2 bh

b

(2) Right triangle:

c =VaJ + b1

a = Vc1 - b2

b =T/c3 - a3 a

b

A = irr7

A = 0.7854 D3

C = irD

(3) Circle:

377

378

(4) Segment of circle: L

rrraa ra sin a

360 2

2trra

360 a = angle- in degrees

(5) Sector of circle:

rL irr* a

2 = 360

(6) Regular polygons. The area of any regular polygon (all sides equal, all angles equal) is equal to the product of the square of the lengths of one side and the factors shown in table 16-13. Example problem: Area of a regular octagon having 6-inch sides is 6 x 6 x 4.828, or 173.81 square inches. See factors in table.

(7) Rectangle and parallelogram A = ab

b

(8) Trapezoid: A = 'Aalb, + b2 )

b

(9) Irregular Jigures. Measure widths or offsets regularly spaced along any straight line, and apply one of the following,

(a) Trapezoidal rule A = one-half the interval between offsets times sum of two end widths plus twice the sum of the intermediate widths.

(b) Simpson's rule (Assumes lateral boundaries are parabolic curves.) A = one-third the interval between offsets times sum of two end widths plus twice the sum of the odd widths, except first and last (3rd, 5th, 7th, etc.) plus 4 times the sum of the even widths (2nd, 4th, 6th, etc.)

Note. The above rule required an odd number of widths. If there ¡san even number, compute separately the area of a trapezoid at one end.

(12) Prism or cylinder: V = a x area of base

(10) Cube: V = b3

(11) Rectangular parallele) V = ab, b,

(13) Pyramid or cone: V (1/3)a x area of base

379

380

(14) Sphere:

V= (4/3)7rr3 = — 6

A = 4^r3

(15) Prismoidal section. V = one-sixth the length times (sum of the end areas plus 4 times the midsection area)

Table 16-13 Polygon Factors

No. of sides Factor No. of sides Factor

0.433

1.000

1.720

2.598

3.634

8

9

10

11

12

4.828

6.182

7.694

9.366

11.196

16-11. TROOP MOVEMENT FACTORS

a. Rates of March See table 16—14.

b ' March Formulas. See table 16—15.

16-12. INFANTRY WEAPONS

See table 16-16.

Table 16-14 Rates of Marches

Unit

Average Rates of March (KMPH)^

On Roads Day Night

Cross-country

Day Night

Days March Kilo meters

Foot troops

Trucks, general

Tracked vehicles

Truck-drawn artillery

Tractor- drawn artillery

40

24

40

32

3.2

40 (lights) 16 (blackout)




2.4

12

16

12

16

1.6

8

20-32

280

240

280

240

This table is for general planning and comparison purposes. All rates given are variable in accordance with the movement conditions as determined by reconnaissance. •y zThe$e rates include normal periodic rest halts.

381

382

Table 16—15. March Formulas and Factors

METRIC CONVERSION FACTORS SEE TABLE 16—19

FOR TIME DISTANCE (TD). TD (HOURS) = D (KILOMETERS)

R (KILOMETERS PER HOUR)

FOR TIME LENGTH (TL) (FOOT COLUMN). TL (MIN) = RS (ROAD SPACE) X FACTOR

RATE ( KMPH)

4.0

3.2

2.4

1.6

FACTOR

.0150

.0187

.0250

.0375

FOR ROAD SPACE (RS) OF FOOT TROOPS: RS (METERS) = (NO. OF MEN X FACTOR) 4 DISTANCES BETWEEN UNITS

FORMATION

SINGLE FILE COLUMN OF TWO'S

2.4

1.2

5 M/MAN

5.4

2.7

FOR TIME LENGTH (TL) VEHICLES (OPEN COLUMN). TL (MINUTES) = (NO. OF

VEHICLES X FACTOR) + TI'S (TIME INTERVALS BETWEEN UNITS)

RATE (KMPH)

16

24

32

40

M/VEH

100 100 100 100 100

.3750

.2500

.1875

.1500

.1250

FOR TIME LENGTH (TL) OF MOTORS (CLOSE COLUMN). TL (MINUTES) = (NO OF

VEHICLES X 12 ) + TI'S

FOR COMPLETION TIME (CT): CT = IP TIME + TL + TD + SCHEDULED HALTS

KAMPLE : HR MIN

07 45 IP TIME (CLOCK TIME)

01 12 TL OF COLUMN ( 1 HR /% 12 MIN)

05 55 TD (IP TO RP, 5HRS 55MIN) 01 00 MEAL HALT (ONE HOUR)

CT = 14 112 OR 1552 HOURS

FOR ROAD SPACE (RS) OF VEHICLES.

RS (KILOMETERS = TL (MIN) X R (KILOMETERS PER HOUR)

60 (MINUTES/HO UR)

Table 16-16. Characteristics of Infantry Weapons and Ammunition

UNLOADED WEIGHT

LBS

METHOD OF

OPERATION

CYCLIC ICI / OR MAX (Ml RATE OF

IRF

MAX/MAX EFFECTIVE

RANGE (METERS)

AMMUNITION PACK

AMMUNITION WEIGHT

(LBSl (PACKED!

BASIC LOAD OF AMMO PER MAN'

WPN

PISTOL M1911 A1 CAL. 45

7 RD MAG

50 RDS/BOX 20 BOX/CAN

2 CAN/CASE

RIFLE M 14 M 14 A1 7.62 MM

9.B4

12.12

20 RO MAG

GAS SEMI-AUTO A AUTO

I72S/460 1725/7001 SA)

/460(A)

5 RD CLIPS 12 CLIPS/BAND

7 BAND/CAN 2 CANS/CASE

SELECTOR MUST BE NSTALLED BYPOO

AVAILABLE WHEN USED AS AUTOMATIC RIFLE.

RIFLE M16 A 1 5.56 MM

GAS SEMI-AUTO A AUTO

10 RD CLIPS 14CLIPS/BAND 4 BAND/CAN 2 CANS/BOX

MAY BE ISSUED WITH A BYPOD WHEN USED AS AR

MACHINE GUN. M60 7.62 MM

BELT METALIC SPLIT LINK

GAS AUTO

550(C) 220/BELT 1 BELT/CAN 4 CANS/BOX

EFFECTIVE RANGE BASED ON GUNNERS ABILITY

MACHINE GUN, HB. M2. CAL

MG-64 MT-44

BELT- METALIC SPLIT LINK

RECOIL SEMI-AUTO

A AUTO

6600/725 AA’

/ I630GND

105/BELT 1 BELT/CAN 2CANS/CASE

2,100/ WPN

USED IN ANTI AIRCRAFT OR GROUND ROLE

SHOTGUN RIOT TYPE 12 GAGE PUMP

5 RD TUBE

MANUAL (PUMP)

DEPENDS ON TYPE OF SHOT

12/CARTON

20 CARTON/ CASE

GRENADE

LAUNCHER

M79/M20J 40 MM

SINGLE SHOT

PERCUSSION 40Q/15O-PT TGT

/350-AREA TOTS

12/BAND 12BAND/BOX

9/8ANOO- LEER

MINIMUM SAFE

RANGE:

COMBAT, 31M

TRNG: 80 M ARM DISTANCE

14—2BM

EFFECTIVE BURST RADIUS 5M

383

384

Table 16 — 16. Characteristics oj Infantry Weapons and Ammunition (Con't) UNLOADED

WEIGHT LBS

CYCLIC (C) 3B MAXIM) RATE OF FIRE

MAX/MAX EFFECTIVE

RANGE (METERS)

AMMUNITION WEIGHT

(LBS) (PACKED)

BASIC LOAD OF AMMO PER MAN/

WPN

HAND GRENADE FRAG— M 67 MM WP M U

MINE ANTI- PERS M1B AI CLAYMORE

ROCKET, HEAT M72A1 (LAW) 46 MM

ELECTRICAL IMPACT FUZE

-5 SEC DELAY

CONTROLLED C ELECTRIC OR TRIPWIRE DETONATION

APPROX 35MOEPEN -DENT ON THROWING DISTANCE OF INDI- DIVIDUAL

I /CTN 30 CTNS/BOX

1/KIT (COM PL ETE) 6 KIT&/CTN

SINGLE SHOT THROW AWAY

27 1/ 120

10/NON- DIV ENGR BN 2/ TRACK VEF (MECH DIV ENGR BN) IS/ DIV ENGR BN

BURSTING RADIUS

2SM ( 6QSEC

BURN TIME)

WHEN EMPLOYED WITH TRIPWIRE MUST BE TREAT ED AS A MINE AND ITS LOCATION RECORDED A RE PORTED DIREC- TIONAL FRAG-60° SECTOR WITH

30 METER RADIUS 16M LETHAL ZONE (BACK A SIDES) AND 100 M BACK BLAST DANGER ZONE

BACK BLAST AREA: ISM DANGER ZONE, 2SM CAUTION ZONE FRONT SITE GRADUATED TO 323 M. M72 ISSUED AS AMMUNITION ‘WEIGHT IS LOAD-

ROCKET LAUNCHER M302 A M202AI 4 TUBE M MM

(FLAME)

4 RD CLIP

RECOILESS SEMI-AUTO

200 PT TGTS 750/ AREA

TGTS 2QMINIMUM

4 RDS/CLIP 4 CLIPS/BOX

M74 ROCKET IS A FLAME ENCAPU — LATED RD s.s- I3M ARMING RANGE. BURSTING RADIUS 20 M BACK BLAST ZONE 40 M

Table 16—16. Characteristics of Infantry Weapons and Ammunition (Con’t)

JNLOADEO WEIGHTS

PORTABLE FLAME THROWER ABC. M 9—7

SELF PROPELLED FLAME THROWER M132A—1

MORTAR

M 29, WITH MOUNT M 23 AÎ SIMM

MORTAR M 30. WITH MOUNT- M24A 1 ♦—2 IN.

TYPE OF

FEED

CYCLIC (C)/ OR MAX (M) RATE OF FIRE

BARREL 28 BIPOD 40 SIGHT 4 BASE 26

FUEL PROPEL- LED BY CAS UNDER PRES- SURE

FUEL PROPEL- LED BY GAS UNDER PRES SURE

MUZZLE LOADING BY HAND

SECONDS CONTINUOUS

iLECTRICAl

BARREL- 137

BRIDGE- 170

BASE- 193 STANDARD-

60 ROTATOR-

90

MUZZLE LOADING BY HAND

DROP FIRE

MAX/MAX EFFECTIVE

RANGE (METERS)

32 SECONDS FOR CONTIN -UOUS DISCHARGE

12(M) FOR 2 MIN

8(M) FOR 1 MIN&9/MIN FOR 6 MIN

AMMUNITION PACK

AMMUNITION WEIGHT

(LBS) (PACKED)

4 GALS OF THICKENED FUEL

200 GALS OF THICKENED FUEL

1/PER CARTON 4/CTNS/BOX

BASIC LOAD OF AMMO PER MAN/

WPN

IGNITION CYL-8, PEPTIZER- 1 GAL, THICKENER-

10 LBS

920 MIN- IMUM

5650/3650

MAX

1 RD/ PER CTN

HE I LLUM SMOKE GAS

26 28 24

’INCLUDES WEIGHT OF MM3 PERSONNEL

CARRIER

EFFECTIVE BURSTING AREA: 25X 20M

40 X 20 40—90 SECONDS

H. HD, ft HT

385

386

16-13. REQUESTING AND ADJUSTING FIELD ARTILLERY FIRE

a. For details refer to TC 6—135. b. The call for fire:

Element Example

Identification of Observer "DELTA SIX FOXTROT ONE EIGHT, THIS IS ALPHA FIVE CHARLIE TWO FOUR!'

Warning Order Direction *1 (in mils)

Location (Grid Coordinate or Shift from Known Point *2)

Description of Target

Method of Engagement

( 1 ) Type of Adjustment (2) Trajectory (3) Ammunition

(a) Type of Projectile (b) Type of Fuze

(4) Distribution of Fire (5) Methods of Fire

FIRE MISSION "DIRECTION 4760" (Between 0—6400)

"GRID NV 64353797" or "FROM HILL 479, RIGHT 110, ADD 400"

"15 MAN PATROL IN OPEN"

Area Fire High Angle

HE VT IN Effect Converge Adjust Fire

NOTE. 1. In the Field Artillery, azimuth is stated as direction and is given in degrees or in mils (1 mil = 1/6400 of a circle). Direction can be taken from a map or compass. The following are examples of reporting the direction to the target:

1. Grid azimuth from observer to target—Direction 4310. 2. Magnetic azimuth from observer to target—Magnetic Direction 2450.

NOTE- 2. In order to locate a target by a shift from a known point, fire direction center personnel must have the location of the known point plotted bn their charts or must be able to identify the known point on their maps. Prominent terrain features, registration points, and previously fired targets are commonly used as known points.

NOTE: 3. Desired accuracy azimuth - nearest 10 mils grid - 8 digit coordinate distance -■ nearest 100 meters

c. Mil Relation for Computing Deviation Corrections. (See figure 16- 14)

W = 3.3 x 20

W 8 66 meters • round up to 70

m - Angular deviation in mils

W 8 Distance in meters from burst/known point to target

R 8 Range to target in thousands of meters

W = R x m

KNOWN POINT

Figure 16—14. Mil relation for computing deviation corrections

388

d After initial call for fire to the fire direction center (FDC), subsequent corrections are requested as shown in figure 16—15.

ROUND NO. 1 : Left 70, drop 400

(3) Confirm for effect during adjustment when (a) Split a 100 meter bracket (b) Obtain a target hit (c) Obtain a correct range spotting

Figure 16—15. Observer procedures for adjusting field artillery fires.

ROUND NO. 4: Add 50. Fire for effect

ROUND NO. 2: Add 200

ROUND NO. 3: Drop 100

RULES: ( 1 ) Keep rounds on observer-target line. (2) Bracket target during adjustment.

e. Angle between target and burst is read in mils, and then distance is determined by multiplying mils by range and then dividing by 1000.

20 mils x 3300 meters Example: 66 meters

1000 See figure 16—16 for hasty method for estimating angle in mils:

ISO

300 '2 SA

è loo,'

!>] 30

NOTE: ARM MUST BE FULLY EXTENDED.

Figure 16—! 6. Hasty method for estimating angle in mils.

390

/. Field Artillery Weapons

TyPe

105 mm 155 mm 155 mm SP 175 mm

8 inch g. Field Artillery Ammunition.

HE — high explosive WP — white phosphorous SMK — smoke, all colors HEAT/HEPT — antitank APERS — beehive GAS — persistant and nonpersistant Illumination

Range

11,500 meters 14,600 meters 18,100 meters 32,700 meters 16,800 meters

h. Fuzes. Type Fuze

Impact

Quick Concrete Piercing Delay

Time (airburst)

Mechanical

Variable (VT)*

Usage Personnel/material

Pill boxes, bunkers, and dugouts.

Personnel in open or i n entrenchments

Preferred

16 -14. MAP READING

A map is a graphic representation of a portion of the earth's surface drawn to scale on a plane.

a. " Types of Maps. (1) Planimetrie Map. Presentation of only the horizontal positions

for the detail plotted, with the omission of relief in a measurable form. (2) Topographic Map A map which portrays relief in a measurable

form, as well as the horizontal positions of the details plotted. (3) Plastic Relie) Map. A topographic map preprinted on plastic

materials in a three dimensional form so that the user can readily see variation in elevation.

(4) Photomap. A reproduction of an aerial photograph or a mosaic made from a series of aerial photographs upon which grid lines, marginal data, place names, spot elevations, boundaries, and scale have been added. Usually supplement other maps of an area.

(5) Pictomap. A photomap-type product which stresses the use of photolithographic operations rather than the conventional techniques used for preparation of standard maps. Heights of map features are accentuated pictorially, while terrain and vegetation are shown in near natural colors (usually published at 1:25,000 scale and larger).

b Map Scales. ( 1 ) Small Scale Maps. 1:600,000 through 1:5,000,000 for strategical

studies at high command echelons. (2) Medium Scale Maps. 1:75,000 to 1:600,000 used for planning

operations including road movements. (3) Large Scale Maps. 1:1,000 to 1:75,000 used to meet the tactical,

technical, and administrative needs of field units.

c. Map Colors. (1) Black. Man-made features, marginal data, and grid. (2) Brown. Terrain features and contour lines depicting elevations. (3) Green Vegetation features. (4) Blue Water features. (5) Red. Main roads and built-up areas.

391

d Map Marginal Data Marginal data, in.the form of diagrams.'pictures, scales and text, are printed on the sheet outside the margin of the map. Provides the user with everything needed to fulfill his map reading requirements. Data of critical importance to the Combat Engineer are:

(1) Grid Reference Box (usualh located in the lower center margin). Contains information for composing grid reference and pirovides a step by step example, using a sample point on the map. Includes Grid Zone Designation (Critical if area of operations includes more than one Grid Zone.)

(2) Bar Scales (usually located in the lower center margin) Graphical distance scales for determining ground distance.

(3) Contour Interval (usually located in center lower margin below the Bar Scutes). Identifies the vertical distance between contour lines.

(4) Legend (usually located in the lower lejt margin) Illustrates and identifies topographic symbols used on the map.

(5) Declination Diagram (usually located in the lower right margin) Graphically illustrates the relationships between Grid North (symbolized by the letters GN), True North (symbolized by a star), and Magnetic North (symbolized by a half arrowhead). Typical Declination diagrams are shown in Fig. 16- 17. Of particular interest to the military user is the relationship of Grid North to Magnetic North, since this defines the relation of Azimuth directions on the map (grid) to an Azimuth obtained with a compass (magnetic). This relationship (the G-M angle), is expressed in degrees and minutes and accompanies the Declination Diagram. Most maps also contain a note for converting from Grid to Magnetic Azimuth and from Magnetic to Grid Azimuth as shown in Figure 16- 17. When the note is not given, conversion must be determined based on the Declination diagram.

NOTE Declination Diagrams and G-M Angles vary from map to map. Users should exercise extreme care to insure that the proper conversions from Grid to Magnetic Azimuth or Magnetic to Grid Azimuth are used.

e. Map Orientation Before any map can be used it must be oriented with the ground; that is, when the map is horizontal, its north and south corresponds to north and south on the ground. Two principal methods of map orientation are:

( 1 ) Compass (a) Place the compass so that the index line on the dial parallels

Grid North.

1960 G. M ANGLE ^ 5° (90 MILS) 2

;r

TO CONVERT A MAGNETIC AZIMUTH TO A GRID AZIMUTH SUBTRACT G-M ANGLE\

TO CONVERT A GRID AZIMUTH TOA MAGNETIC AZIMUTH ADD G-M ANGLE

GRID CONVERGENCE Io 19' (23 MILS) FOR CENTER OF SHEET

1960 G. M. ANGLE ’

7 1/2° (130 MILS)

GRID CONVERGENCE

2° 26' (43 MILS) FOR CENTER OF SHEET

GRID CONVERGENCE

Io 24'(25 MILS) FOR CENTER OF SHEET\

TO CONVERT A GRID AZIMUTH TOA MAGNETIC AZIMUTH ADD G-M ANGLE

TO CONVERT A MAGNETIC AZIMUTH TO A GRID AZIMUTH SUBTRACT G-M ANGLE

> o z m H n z o 9

1960 G.M. ANGLE

8° (140 MILS)

TO CONVERT A MAGNETIC AZIMUTH TO A GRID AZIMUTH ADD G-M ANGLE

TO CONVERT A GRID AZIMUTH MAGNETIC AZIMUTH SUBTRACT G-M ANGLE

Figure 16-17. Declination diagrams.

393

394

<b) Rotate the map and compass until the directions of the black index line and the compass needle match the directions on the declination diagram.

(2) Terrain Association. (a) Carefully examine both the map and the ground to find the

linear features (roads, railroads, fences, power lines, etc.) or prominent objects which can be located on both.

(b) Align the feature on the map with the feature on the ground. NOTE. Map Orientation by terrain association results in gross

orientation which will usually be sufficiently accurate for land navigation but may not be sufficient for targeting. The use of more than one linear feature or prominent object for orientation will not only preclude reversal of direction but also refine the map-ground orientation.

/. Scale and Distance (Representative Fraction). (1) The scale of a map expresses the ratio of horizontal distance on

the map to the corresponding horizontal distance on the ground using the same unit of measurement for both. The representative fraction (RF) is

always written with the map distance as: An RF of —-— or 1/50,000 or 50,000

1:50,000 means that one (1) unit of measurement on the map equals a corresponding number of like units of measurements (50,000) on the ground.

(2) The ground distance between two points on a map is determined by measuring the distance between the points and multiplying the map measurement by the denominator of the RF. Example:

a. Map distance between two pints = 5 units (i.e. 5 in.). b. The RF of the map is 1:50,000, therefore, c. 5 x 50,000 = 250,000 units of ground distance (250,000 inches)

(3) Further data on finding unknown RF's, ground or map distances, is explained in FM 21-26 and table 16--17.

g. Contours. A contour line is a line representing an imaginary line on the ground along which all points are of the same elevation.

(1) Contour lines evenly spaced and wide apart indicate a uniform gentle slope.

(2) Contour lines evenly spaced and close together indicate a uniform steep slope. The closer the contour lines to each other the steeper the slope.

Table 16-17. Map Distance Conversion

REPRESENTATIVE FRACTION (RF)

35,000 50.000 75.000 100,000 750,000 500.000 1,000,000

INCHES

FEET

YARDS

METERS

MILES

KILOMETERS

75,000

7,003

694

635

0 4

50.000 4,167

1,309

1,770

0.0

1 3

75,000

6,350

3,003

1.905

l 7

1.91

ONE CENTI METER

INCHES

FEET

YARDS

METERS

MILES

KILOMETERS

9,843

830

373

750

0 16

75

19,685 1,640

547

500 0 3

79,578 7,460

070

100,000

0,333

7.770

7,540

1.6

3.54

39.370 3,381

1.094

1,000

0 6 I 00:

700,000

16.667

5.555

78,740 6,567

7,187

750,000

70.033

6.944

6.350

4

6 35

500,000

41,667

13.088

17,700

0 13.7

98.475 0,70?

7,734

7,500

1 5

196,850 16,404

5,460

5,000

1,000.000

03.333

37.776

75,400

16

75 4

393,700

33.808

10.936

10,000

h Slope. The rate of rise and fall of a ground form is known as its slope. Slope may be expressed in several ways but all depend upon a comparison of vertical distance (VD) to horizontal distance (HD). VD is the difference between the highest and lowest elevations of a slope and is determined from the contour lines. HD is the horizontal ground distance between the highest and lowest elevations of the slope and is measured using the bar scale of the map. The VD and HD must be expressed in the same unit of measurement.

(1) A common expression of slope is as a percent (%) which indicates the number of vertical units of elevation to every hundred units of horizontal distance. Whenever a gradient or percent is used, a plus or minus sign must be given to indicate whether the slope is rising or falling.

(2) Slope may also be èxpressed in degrees, a unit of angular measure. VD

Determine the value of — in decimal form. This will be the tangent of the H D

slope angle. The slope angle can then be found in table 16-12. The

VD approximate slope angle may be calculated by multiplying the value of HD

by 57.3. This method should only be used for slope angles under 20°.

395

396

Aerial Photography As Supplenients/Substitutes (1) General Current aerial photography supplements printed maps

by showing changes since the map was compiled. Vertical aerial photography (camera aimed straight down) is most often used for this purpose since scale, grid, and orientation are most easily correlated to a map (and therefore the ground). Only an approximate scale of most photographs can be determined, however, for most military applications, this approximate scale is sufficient. Methods of determining scale are:

(a) Photo-ground comparison method , Photo Distance

Scale (RF) = Ground Distance

<b) Photo-map comparison method. , , Photo Distance

Scale (RF) = :: Map Scale (RF) Map Distance

(c) Focal length method F (Focal Length)

Scale (RF) = —2 , HIFlight Altitude) — h(average ground elevation)

(2) Point designation grid. Grids are rarely printed on aerial photography. It is a user responsibility to construct a world-wide standard Point Designation Grid on each photo in the following manner (see fig. 16- 18).

(a) Hold the photograph so that marginal information, regardless of where it is located, is in the normal reading position, draw straight lines across the photograph joining opposite reference marks (Fiducial marks).

(b) Space grid lines, starting at the center lines, 4 cm. apart, (a distance equal to 1,000 meters at a scale of 1:25,000).

(c) Number each centerline "50" and give numerical values to the remaining horizontal and vertical lines so that they increase to the right and up.

(3) Photo grid coordinates The Point Designated Grid (PDG) is used in the same manner as a map -READ RIGHT-UP. A Grid Coordinate using the Point Designation Grid consists of:

(a) The Letters "PDG". (b) This mission and photo number (from the photo margin). (c) The appropriate number of digits (READ RIGHT-UP) to locate

the point on the photograph.

/ Orientation (see pora 16—14e). Photographs are normally oriented by construction of a Magnetic North arrow on the photo so that the photo can be quickly oriented with the ground using a compass.

(1) Photo-ground. Orientation with the ground can be accomplished by compass or terrain association methods as in paragraph 16-14e. Magnetic North is then constructed by aligning the compass with 0° or 360° and drawing a line along the graduated straight edge.

ÍMAfcGiNAi INFORMATION) ¿MARGINAL INFORMATION)

Utij STEP (T) STEP @

. _ .¿MARGINAL INFORMAMON> “I 1 IMA MON') I _ .{MARGINAL INFORMATION y

STEP @ 47 44 49 30 51 32 51

STEP @

Figure 16-18. Construction of point designation grid.

397

(2) Photo-map. (a) Carefully examine the photograph and the map to find two

features (road junctions, bridges, water towers, etc.) which can be located on both the photo and the map.

fbj Connect the two features on both map and photograph with straight lines.

fc> Using the declination diagram, measure the grid azimuth of the line drawn on the map and determine the corresponding magnetic azimuth.

(d) Transfer this magnetic azimuth to the straight line on the photo.

(e) Based on this magnetic azimuth construct Magnetic North on the photo.

16-15. PROJECT MANAGEMENT

a. General. The following technique gives supervisors the ability to plan, schedule and control any engineer project and will point out which areas should be carefully controlled. Detailed references are found in TM 5-333.

b. Preliminary Planning. ( 1 ) Receive job directive. (2) Study directive and accompanying plans and specifications. (3) Conduct site investigation to determine how the actual site

conditions will affect the job. Typical factors are: (a) Terrain (b) Drainage (c) Accessibility (d) Soil Conditions (e) Existing Facilities (1) Natural Resources (g) Weather (h) Enemy

c. Task List. (1) Break the assigned job into the separate operations or tasks

necessary to successfully complete the job. The number and detail of these tasks will vary from job to job.

(2) Each separate task must be a time consuming part of a job which has a definable beginning and end.

(3) follows:

Task A. B.

C. D. E. F. G. H. I.

J. K. L. M. N.

The tasks Involved in building a timber trestle bridge could be as

Recon site Secure and prepare site Precut caps, sills, and scabs Precut stringers, decking, and lateral braces Place abutments Bridge layout Construct first trestle bent Continue trestle bent const.

Place stringers first span Continue placing stringers Deck first span Continue decking Place curb and riser Place treadway

d. Logic From the task list determine the essential relationships between the tasks. To accomplish this the following questions should be asked for each task:

( 1 ) Is this task necessary to begin the project? (2) What tasks must be finished before this one begins? (3) What tasks may either start or finish at the same time as this one? (4) What tasks cannot begin until this is finished? (5) Does this tasks denote project completion?

e. Lsmnanitg (Detailed references in TM 5—302 and TM 5—333) (1) Once the tasks are determined, each task requires an estimate of

materials and equipment/manpower needs. Adjust data to reflect appropriate waste and efficiency factors.

(2) Man-hours, man-days, machine-hours or machine days are divided by the men or equipment in your crew to obtain the duration of the task.

16-16. CONVERSION FACTORS

See table 16-18.

399

400

Table 16—18. Conversion Factors

Multiply by to obtain

Acres acres acres acres acres acre—feet acres atmospheres atmospheres atmospheres atmospheres

Board—feet British thermal units British thermal units British thermal units B.t.u. per min B.t.u. per min B.t.u. per min bushels

43.560 4,047 1,562 x 10-3

5645.38 4,840 43.560 100 76.0 29.92 33.90 14.70

144 sq. in. x 1 in. 0.2520 777.5 2.928 x 10“ 4

0.02356 0.01757 17.57 1.244

square feet, square meters, square miles, square varas, square yards, cubic—feet, square meters, cms. of mercury, inches of mercury, feet of water, pounds per sq. inch.

cubic inches. kilogram-calories, foot-pounds, kilowatt- hours, horse- power kilowatts, watts, cubic feet.

Centares centigrams centiliters centimeters centimeters centimeters centimeters centimeters-grams centimeter—grams centimeters of mercury centimeters of mercury centimeters of mercury centimeters of mercury

1 0.01 0.01 0.3937 0.01 393.7 10 10-5

7.233 x 10 “5

0.01316 0.4461 136.0 27.85

square meters. grams. liters. inches. meters. mils. millimeters. meter-kilograms. pound—feet. atmospheres. feet of water. kgs. per square mater. pounds per sq. foot.

Table 16—IS. Conversion Factors (Con't)

Multiply

centimeters of mercury centimeters per second circular mils

cord—feet cords cubic centimeters cubic centimeters cubic centimeters cubic centimeters cubic feet cubic feet cubic feet cubic feet cubic feet cubic feet cubic feet per minute cubic feet per minute cubic feet per minute cubic feet per minute cubic inches cubic inches cubic inches cubic meters cubic meters cubic meters cubic meters cubic yards cubic yards cubic yards cubic yards per minute cubic yards per minute

by

0.1934 0.6 0.7854

4 ft. x 4 ft. x 1 ft. 8 ft. x 4 ft. x 4 ft. 6.102 x 10T2

10-6

2.642 x 10-4

10-3

2.832 x 104

1.728 0.02832 0.03704 7.481 28.32 472.0 0.1247 0.4720 62.4 16.39 5.787 x 10-4

0.01732 106

35.31 1.308 264.2 27 0.7646 202.0 0.45 3.367

to obatin

pounds per sq. inch, meters per minute, square mils,

cubic feet, cubic feet, cubic inches cubic meters, gallons, liters, cubic cms. cubic inches, cubic meters, cubic yards, gallons, liters. cubic cms. per sec. gallons per. sec. liters per second lbs. of water per min. cubic centimeters, cubic feet, quarts (liq.). cubic centimeters, cubic feet, cubic yards, gallons, cubic feet, cubic meters, gallons. cubic feet per second, gallons per second.

401

Table 16—18. Conversion Factors (Con ’!)

Multiply by

Decigrams 0.1 deciliters 0.1 decimeters 0.1 degrees (angle) 60 degrees (angle) 0.01745 degrees (angle) 3600 dekagrams 10 dekaliters 10 dekameters 10 drams 1.772 drams 0.0625

Ergs 9.486 x 10-11

Fathoms feet feet feet feet of water feet per minute feet per minute feet per minute feet per second feet per second feet per second feet per second feet per 100 feet foot-pounds foot-pounds foot-pounds foot-pounds foot-pounds foot-pounds per minute foot-pounds per minute

6 0.3048 .36 1/3 0.4335 0.5080 0.01667 0.01136 1.097 0.5921 18.29 0.6818 1 1.286 x 10-3

1.356 x 107

5.050 x 10-7

3.241 x 10~4

3.766 x 10-7

1.286 x 10-3

3.030 K 10-5

to obtain

grams. liters. meters. minutes. radians. seconds. grams. liters. meters. grams. ounces.

British thermal units.

feet. meters. varas. yards. pounds per sq. inch, centimeters per sec. feet per second, miles per hour, kilometers per hour, knots per hour, meters per minute, miles per hour, per cent grade. British thermal units, ergs. horse- power—hours, kilogram—calories, kilowatt-hours. B.t. units per minute, horse power.

Table 16—IS. Conversion Factors (Con't)

Multiply by

foot—pounds per minute 3.241x10“^ foot-pounds per minute 2.260 x 10—® furlongs 40

Gallons gallons gallons gallons gallons gallons per minute

gills grains (troy) grains (troy) grains (troy) grams grams grams grams grams grams grams gram-calories gram-centimeters gram—centimeters grams per cm grams per cu. cm

3785 0.1337 231 3.785 x 10-3

4.951 x 10-3

2.228 x 10-3

0.1183 1 0.06480 0.04167 980.7 15.43 IQ“3

103

0.03527 0.03215 2.205 x 10-3

3.968 x 10-3

2.344 x 10-8

IO-5

5.600 x 10-3

62.43

Hectares hectares hectograms hectoliters hectometers hectowatts

2.471 1.076 x 105

100 100 100 100

to obtain

kg—calories per min. kilowatts. rods.

cubic centimeters, cubic feet, cubic Inches, cubic meters, cubic yards, cubic feet per second,

liters. grains (av.). grams. pennyweights (troy), dynes. grains (troy). kilograms. milligrams. ounces. ounces (troy). pounds. British thermal units, kilogram—calories, kilogram—meters, pounds per Inch, pounds per cubic foot.

acres. square feet. grams. liters. meters. watts.

403

Table 16—18. Conversion Factors (Coit't)

Multiply

horse- power horse—power horse—power horse—power horse—power horse—power horse—power

inches inches inches inches

inches of mercury inches of mercury inches of water inches of water inches of water inches of water inches of water

Joules joules joules joules joules joules

Kilograms kilograms kilograms kilograms kilogram- calories kilogram—calories ti logram- calories

by to obtain

42.44 33,000 550 1.014 10.70 0.7457 745.7

B.t. units per min. foot-pounds per min. foot-pounds per sec. horse-power (metric), kg.-calories per min. kilowatts, watts.

2.540 103

.03 0.03342

1.133 70.73 0.002458 0.07355 0.5781 5.204 0.03613

centimeters. mils. varas. atmospheres,

feet of water, pounds per square ft. atmospheres, inches of mercury, ounces per square in. pounds per square ft. pounds per square in.

9.486 x 10-"4

107

0.7376 2.390 x 10'“4

0.1020 2.778 x 10~4

British thermal units, ergs. foot-pounds, kilogram- calories, kilogram—meters, watt—hou rs.

980,665 103

2.2046 1.102 10-3

3.968 3088 1.588 x 10'3

dynes, grams, pounds, tons (short). British thermal units, foot-pounds, horse power- hours.

Tubte 16—IS. Conversion l'aclors (Coii't)

Multiply

kilogram—calories kg.—calories per min kilogram—meters kilogram—meters kgs. per cubic meter kgs. per cubic meter kgs. per square meter kgs. per square meter kgs. per square meter kgs. per square meter kgs. per square meter kiloliters kilometers kilometers kilometers kilometers kilometers per hour kilowatts kilowatts kilowatts kilowatts- hour kilowatts-hours knots knots

Links (engineer's) links (surveyor's) liters liters liters liters per minute liters per minute

by to obtain

1.162 x 10 0.06972 9.302 x 10

,-3

3

5 ,-3 -3

9.807 x 107

10' 3

0.06243 9.678 x 10 3.281 x 10 2.896 x 10 0.2048 1.422 x 10-3

103

105

3281 103

0.6214 0.5396 56.92 4.425 x 104

1.341 3415 2.655 x 106

1.853 1.152

kilowatt-hours. kilowatts. British thermal units, ergs. grams per cubic cm.' pounds per cubic foot, atmospheres, feet of water, inches of mercury, pounds per square ft. pounds per square in. liters. centimeters. feet. meters. miles. knots per hour. B.t. units per min. foot-pounds per min. horse-power. British thermal units, foot-pounds, kilometers per hour, miles per hour.

12 7.92 103

0.2642 1.057 5.885 x 10 4.403 x 10

-4 -3

inches. inches. cubic centimeters, gallons, quarts (liq.). cubic feet per second, gallons per second.

405

Table 16-IS Conversion Factors (Cun't)

Multiply

Meters meters meters meters meters meters microns miles miles miles miles per hour miles per hour miles per hour milliers milligrams milliliters millimeters millimeters millimeters mils mils minutes (angle) minutes (angle) myriagrams myriameters myriawatts nautical miles nautical miles

Ounces ounces ounces ounces

by

100 3.2808 39.37 10-3

103

1.0936 10-6

5280 1.6093 1760 1.467 1.6093 0.8684 103

10-3

10-3

0.1 0.03937 39.37 0.002540 10-3' 2.909 x 10-4

60 10 10 10 1.152 2027

8 437.5 28.35 0.0625

to obtain

centimeters, feet, inches, kilometers, millimeters, yards, meters, feet. kilometers. yards. feet per second. kilometers per hour. knots per hour. kilograms. grams. liters. centimeters. inches. mils. centimeters. inches. radians. seconds (angle). kilograms. kilometers. kilowatts. miles. yards.

drams. grains. grams. pounds.

Tabic 16- 18. Conversion Factors (Con't)

Multiply

ounces (fluid) ounces (troy) ounces (troy) ounces (troy) ounces (troy)

Perches (masonry) pints (dry) pints (liq.) pounds pounds pounds pounds pound—feet pound-feet pound—feet pounds of water pounds of water pounds of water pounds per cubic foot pounds per cubic inch pounds per foot pounds per square foot pounds per square foot pounds per square inch pounds per square inch pounds per square inch pounds per square inch pounds per square inch

Quadrants (angle) quadrants (angle) quadrants (angle) quarts (dry) Quarts (liq.)

by

1.805 480 31.10 20 0.08333

24.75 33.60 28.87 444,823 453.6 16 32.17 1.356 x 107

13,825 0.1383 0.01602 27.68 0.1198 16.02 27.68 1.488 0.01602 4.882 0.06804 2.307 2.036 703.1 144

90 5400 1.571 67.20 57.75

to obtain

cubic inches, grains (troy), grams. pennyweights (troy) pounds (troy).

cubic feet. cubic inches. cubic inches. dynes. grams. ounces. poundals. centimeter-dynes, centimeter—grams, meter—kilograms, cubic feet, cubic inches, gallons. kgs. per cubic meter, grams per cubic cm. kgs. per meter, feet of water, kgs. per square meter, atmospheres, feet of water, inches of mercury, kgs. per square meter, pounds per sq. foot.

degrees, minutes, radians, cubic inches, cubic inches.

407

Table 16-18 Conversion Factors (Con'i)

Multiply

Radians radians radians reams revolutions revolutions revolutions revolutions per minute revolutions per minute revolutions per minute revs, per min. per min revs, per min. per min revs, per min. per min revolutions per second revolutions per second rods

Seconds (angle) square centimeters square centimeters square feet square feet square feet square feet square feet square inches square inches square kilometers square kilometers square kilometers square kilometers square kilometers square meters square meters

by

57.30 3438 0637 500 360 4 6.283 6 0.1047 0.01667 1.745 x 10~3

0.01667 2.778 x 10-4

360 6.283 16.5

4.848 x 10-6

0.1550 100 2.296 x 10” 5

0.09290 3.587 x 10-8

.1296 1/9 6.452 6.944 x 10-3

247.1 10.76 x 106

106

0.3861 1.196 x 106

2.471 x 10-4

10.764

to obtain

degrees. minutes. quadrants. sheets. degrees. quadrants. radians. degrees per second, radians per second, revolutions per sec. rads, per sec. per sec. revs, per min. per sec. revs, per sec. per sec. degrees per second, radians per second, feet.

radians, square inches, square millimeters, acres. square meters, square miles, square yaras. square yards, square centimeters, square feet, acres. square feet, square meters, square miles, square ycrds. acres. square feet.

Table 16-lÿ Conversion hadurs (Cun't)

Multiply

square meters square meters square miles square miles square miles square miles square miles square yards square yards square yards square yards square yards steradians steres

by

3.861 x 10~7

1.196 640 27.88 x 106

2.590 3,613,040.45 3.098 x 106

2.066 x 10~4

9 0.8361 3.228 x 10~7

1.1664 0.1592 103

to obtain

square miles, square yards, acres. square feet, square kilometers, square varas, square yards, acres. square feet, square meters, square miles, square varas, hemispheres, liters.

Temp. (degs. C.) + 273 1 temp. (degs. C.) + 17.8 1.8 temp. (degs. F.) + 460 1 temp, (degs F.)—32 5/9 tons (long) 1016 tons (long) 2240 tons (metric) 103

tons (metric) 2205 tons (short) 907.2 tons (short) 2000 tons (short) per sq. ft 9765 tons (short) per sq. ft 13.89 tons (short) per sq. in 1.406 x tons (short) per sq. in 2000

2.7777

abs. temp. (degs. C.). temp. (degs. Fahr.). abs. temp. (degs. F.l. temp. (degs. Cent.). kilograms. pounds. kilograms. pounds. kilograms.

pounds. kgs. per square meter, pounds per sq. inch.

10" kgs. per square meter. pounds per sq. inch.

feet. Varas

410

Table 16-18. Conversion Factors (Con’t)

Multiply by to obtain

Watts watts watts watts watts watt—hours weeks

0.05692 107

44.26 1.341 ; 102

3.415 168

10 -3

B.t. units per min. ergs per second, foot-pounds per min. horse—power, kilowatts. British thermal units, hours.

Yards yards yards yards

91.44 3 36 0.9144

centimeters. feet. inches. meters.

NOTE See FM 5—35 for additional conversion factors.

16-17. CONVERSION - ENGLISH UNITS TO METRIC UNITS

See table 16-19.

16-18. TIME DISTANCE CONVERSION

See table 16—20.

Table ¡6-19 Conversion — English Metric System

Length

inches >- cm - ^ inches feet meters meters ^ feet yards — ^ meters meters ^ yards miles ^ kilo-

km . miles

f 1 J)62_

UÍJ 1-24

3 1.86

4 2 49

5 3.11

6 3 73

7 4.35

8 4.97

9 5.59

10 6.21

20 12.43

30 18.64

40 24.85

50 31.07

60 37.28

70 43.50

80 49.71

90 55.92

100 62.14

meters

I ’ i

1Æ1 1_09_

3.22 2.19

4.83 3.28

6.44 4.37

8.05 5 47

9.66 6 56

11.27 7.66

12.87 8 75

14.48 9.84

16.09 10.94

32.19 21.87

48.28 32.81

64.37 43.74

80.47 54.68

96.56 65.62

112.65 76.55

128 75 87.49

144.84 98.42

160.94 109.36

0.91 3.28

~ 1.83 6.56

2.74 9.84

3.66 13.12

4.57 16.40

5.49 19 68

6.40 22.97

7.32 26 25

8.23 29.53

9.14 32.81

18.29 65.62

27.43 98.42

36.58 131.23

45.72 164.04

54.86 196.85

64.00 229.66

73.15 262.47

82.30 295.28

91.44 328.08

Y Y 0.30 0.39

" 0.61 0.79

0.91 1.18

1.22 1.57

1.52 1.97

1.83 2.36

2.13 2.76

2.44 3.15

2.74 3 54

3.05 3.93

6.10 7.87

9.14 11.81

12.19 15.75

15.24 19.68

18.29 23.62

21.34 27.56

24.38 31.50

27.43 35.43

30.48 39.37

Example: 2 inches = 5.08 cm

centi* meters

2.54

¡IjOSj 7.62

10.16

12.70

15.24

17.78

20.32

22.86

25.40

50.80

76.20

101.60

127.00

152.40

177.80

203.20

228.60

254.00

411

412

Table Ib-19 Conversion-English Metric St stem ( Con t)

ONE UNIT (BELOW) 4 EQUALS ►

MM (MILLIMETERS) CM (CENTIMETERS) METERS KM (KILOMETERS)

MM

Ï7 10.

1,000. 1,000,000.

CM

oTT 1.

100. 100,000.

METERS

0.001 0.01 1.

1,000.

KM

0.000,001 0.000,01 0.001 1.

ONE UNIT (BELOW) ^ EQUALS — GM KG METRIC TON

GM (GRAM) KG (KILOGRAMS) METRIC TON

1. 1,000.

1,000,000.

0.001 1.

1,000.

0.000,001 0.001 1.

UNITS OF CENTIMETERS

CM 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.10 INCH 0.04 0.08 0.12 0.16 0.20 0.24 0.28 0.31 0.35 0.39

FRACTIONS OF AN INCH

INCH 1/16 1/8 3/16 1/4 5/16 3/8 7/16 1/2 CM 0.16 0.32 0.48 0.64 0.79 0.95 1.11 1.27

INCH CM

9/16 1.43

5/8 1.59

11/16 1.75

3/4 1.91

13/16 2.06

7/8 2.22

15/16 1 2.38 2.54

Table 76-/9. Conversion—English Metric Systems (Con't)

WEIGHT

^ ounces •y- kilograms

pounds

ounces grams - pounds . kg short ton ■ metric ton - -y short

ton

i 1 1.10

2 2.20

3 3.31

4 4.41

5 5.51

6 6.61

7 _7.72_

[VI ~ 8.82

9 9.92

10 _n.02 _

[20 J” 22.05

30 33.07

40 44.09

50 55.12

60 66.14

70 77.16

80 88.18

90 99.21

100 110.20

» metric ton

I I 0.91 2.20

1.81 4.41

2.72 6.61

3.63 8.82

4.54 11.02

5.44 13.23

_6;35 25^3

7.26 17.64

8.16 19.84

_9.07 22.05

18.14 44.09

27.22 66.14

36.29 88.18

45.36 110.23

54.43 132.28

63.50 154.32

72.57 176.37

81.65 198.42

90.72 220.46

V 0.45 0.04

0.91 0.07

1.36 0.11

1.81 0.14

2.67 0.18

2.72 0.21

3.18 0.25

Ipjal 0.28

¡4.08 0.32 14,54 0.35

0.71

13.61 1.06

18.14 1.41

22.68 1.76

27.22 2.12

31.75 2.47

36.29 2.82

40.82 3.17

45.36 3.53

Example: 28 pounds = 9.07 kg + 3.63 kg = 12.70 kg

grams

28.4

56.7

85.0

113.4

141.8

170.1

198.4

226.8

255.2

283.5

567.0

850.5

1134.0

1417.5

1701.0

1984.5

2268.0

2551.5

2835.0

413

Table 16—19 Conversion—English Metric Systems (Con't)

VOLUME

cu. meters cu. ft - cu. yd cu. ft—vcu.

cu. ft. cu. yd

I fr. cu. meters

I

meters

1 1 0.037 0.028 2 0.074 0_057_

HJJ 0.111 0.085 4 0.148 0.113 5 0.185 0.142 6 0.212 0.170 7 0.259 0.198 8 0.296 0.227 9 0.333 0.255

10 0.370 0.283 20 0.741 0.566 30 1.111 0.850 40 1.481 1.133 50 1.852 1.416 60 2.222 1.700 70 2.592 1.982 80 2.962 2.265 90 3.333 2.548

100 3.703 2.832

27.0 0.76 35.3 _ 54J) 1.53 70.6

ÜL0Ü 2.29 105.9 108.0 3.06 141.3 135.0 3.82 176.6 162.0 4.59 211.9 189.0 5.35 247.2 216.0 6.12 282.5 243.0 6.88 317.8 270.0 7.65 353.1 540.0 15.29 706.3 810.0 22.94 1059.4

1080.0 30.58 1412.6 1350.0 38.23 1765.7 1620.0 45.87 2118.9 1890.0 53.52 2472.0 2160.0 61.16 2825.2 2430.0 68.81 3178.3 2700.0 76.46 3531.4

cu. yd

W

1.31 2.62 3.92 5.23 6.54 7.85 9.16

10.46 11.77 13.07 26.16 39.24 52.32 65.40 78.48 91.56

104.63 117.71 130.79

Example: 3 cu. yd = 81.0 cu ft

Table 16—20. Time Distance Conversion

Miles per

hour Knots

Feet per

Second

Kilometers per

hour

Meters per

Second

1

2

3

4

5

6

7

8

9

10

15

20

25

30

35

40

45

50

55

60

65

70

75

100

0.8684

1.74

2.61

3.47

4.34

5.21

6.08

6.95

7.82

8.68

13.03

17.37

21.71

26.05

30.39

34.74

39.08

43.42

47.76

52.10

56.45

60.79

65.13

86.84

1.4667

2.93

4.40

5.87

7.33

8.80

10.27

11.73

13.20

14.67

22.00

29.33

36.67

44.00

51.33

58.67

66.00

73.33

80.67

88.00

95.33

102.67

110.00

146.67

1.609

3.22

4.83

6.44

8.05

9.66

11.27

12.87

14.48

16.09

24.14

32.19

40.23

48.28

56.33

64.37

72.42

80.47

88.51

96.56

104.61

112.65

120.70

160.94

0.447

0.894

1.34

1.79

2.24

2.68

3.13

S.SS1

4.02

4.47

6.71

8.94

11.18

13.41

15.64

17.88

20.12

22.35

24.59

26.82

29.06

31.29

33.53

44.70

415

416

APPENDIX A

REFERENCES

A—1. ARMY REGULATIONS

AR 310- 25 Dictionary of United States Army Terms AR 310—50 Authorized Abbreviations and Brevity

Codes

A—2. DEPARTMENT OF THE ARMY PAMPHLETS

DA Pam 108—1 Index of Army Motion Pictures and Related Audio-Visual Aids.

DA Pam 310 Series Military Publications Indexes (as applicable)

DA Pam 350-19 Training, Signal Security Instructional Packet

A—3. FIELD MANUALS

FM 3-8 FM 5-1

FM 5—13 FM 5-15 FM 5-20 FM 2-25 FM 5-30 FM 5-31 FM 5-35 FM 5-36 FM 10-13 FM 20-22 FM 20-32

Chemical Reference Handbook Engineer Troop Organizations and Operations The Engineer Soldier's Handbook Field Fortifications Camouflage Explosivesand Demolitions' Engineer Intelligence Boobytraps Engineer's Reference and Logistical Data Route Reconnaissance and Classification Supply and Service Reference Data Vehicle Recovery Operations Mine/Countermine Operations at the Company Level

FM 20-33 FM 21-5 FM 21-6 FM 21-10 FM 21-26 FM 21-30 FM 21-31 FM 21-41

FM 21-60

FM 21-76 FM 24-1 FM 24-18 FM 30-5 FM 30-10 FM 31-60 FM 31-70 FM 32-5 FM 32-6 FM 55-15 FM 101-10-1

Combat Flame Operations Military Training Management Techniques of Military Instruction Field Hygiene and Sanitation Map Reading Military Symbols Topographic Symbols Soldier's Handbook for Defense Against Chemical and Biological Operations and Nuclear Warfare Visual Signals

Survival, Evasion and Escape Tactical Communications Doctrine Field Radio Techniques Combat Intelligence Denial Operations and Barriers River-Crossing Operations Basic Cold Weather Manual Signal Security Signal Security Techniques Transportation Reference Data Staff Officers' Field Manual

A—4. TECHNICAL MANUALS

TM 3—220 CBR Decontamination TM 3—366 Flame Fuels TM 5—200 Camouflage Materials TM 5—210 Military Floating Bridge Equipment TM 5—216 Armored Floating Bridge Equipment TM 5—220 Passage of Obstacles Other Than Minefields TM 5—232 Elements of Surveying TM 5—233 Construction Surveying TM 5—258 Pile Construction TM 5—270 Cableways, Tramways, and Suspension

Bridges

417

418

TM 5-337 TM 5-342 TM 5-349 TM 5-461 TM 5-617 TM 5-618 TM 5-624

TM 5-700 TM 5-725 TM 5-742 TM 5-766 TM 5-277 TM 5-280 TM 5-297 TM 5-302 TM 5-311

TM 5-312 TM 5-315

TM 5-330

TM 5-330-1 TM 5-331A

TM 5-3318 TM 5-331C

TM 5-331D TM 5-331E

TM 5-332 TM 5-333

Paving and Surfacing Operations Logging and Sawmill Operation Artie Construction Engineer Handtools Roofing, Repairs and Utilities Paints and Protective Coating Roads, Runways, and Miscellaneous Pavements, Repairs and Utilities Field Water Supply Rigging Concrete and Masonry Electrical Power Generation in the Field Bailey Bridge Foreign Mine Warfare Equipment Well Drilling Operations Construction in the Theater of Operations Military Protective Construction (Nuclear Warfare and Chemical and Biological Operations) Military Fixed Bridges Firefighting and Rescue Operations in Theaters of Operations Planning and Design of Roads, Airbases, and Heliports in the Theater of Operations Hasty Revetments for Parked Aircraft Earthmoving, Compaction, Grading and Ditching Equipment Lifting, Loading, and Hauling Equipment Rock Crushers, Air Compressors, and Pneumatic Tools Asphalt and Concrete Equipment Engineer Special Purpose and Expedient Equipment Pits and Quarries Construction Management

TM 5-6665-202-15 TM 5-6665-293-13 TM 9-1300-214 TM 9-1375-200

Detecting Set, Mine, (AN/PSS—11 ) Detecting Set, Mine (AN/PRS-7) Military Explosives Demolition Materials

A—5. TRAINING CIRCULARS

TC 6-135 Fire tor Effect, How to be Your Forward Observer

A-6. NATO AGREEMENTS (STANAGS)

2001 2002

2010 2012 2015 2019 2021

2027 2036

2096

2136 2269

Marking Lanes through Minefields Marking of Contamineted or Dangerous Areas Bridge Classification Markings Military Route Signing Route Classification Military Symbols Computation of Bridge, Raft, and Vehicle Classifications Marking of Military Vehicles Land Minefield Laying, Recording, Reporting and Marking Procedures Reporting Engineer Information in the Field Minimum Standards of Water Potability MGD — Engineer Resources

419

420

INDEX

Paragraph

Abatís 2—13, 4—23 Abutment Demolitions 2—10 Activity Symbols 14—11 Aerial Photography 16—14 Aggregate, Estimating Stored Amounts 8—4 Agreements, Standard 1—4 Aircraft Characteristics 10—2 Airfield Repair 10—9 Aluminum Footbridge Data 6—1 Amoebic Dysentery Cysts 16—2 Anchorage Systems 6—5 Antennas 15—2 Antitank Craters 2—14 Areas of Geometric Figures 16—10 Army Track Road 9—7 Artillery Ammunition and Fuzes 16—13 Artillery Fire Adjustments 16—13 Artillery Fire Requests 16—13 Assault Boats 6—1 Attachments, Rigging 11—5

Back Rippers 12—3b Backtrack Loading, Scrapers 12—3b Bailey Bridge 7—9 Bangalore Torpedo 2—1b, 3—10a Barbed Steel Tape 4—12 Barbed Wire

Concertina 4—16 Employment 4-8 Obstacles 4—23 Portable Obstacles 4—22 Requirements 4—10 Tanglefoot 4—21 Ties 4—11

Page

28, 123 18

337° 396 222

2 256 267 132 351 149 341

28 377 254 390 386 386 132 278

295 295 205

3, 75 110

112 105 110 117 106 116 107

Bearing Plate Design 6—7 162 Blade to Blade Dozing 12—3b 295 Block and Tackle 11—2 271 Boom Derrick 11—13 386 Boulder Blasting 2—16 35 Braces for Concrete Forms 8—8a 225 Branch and Duty Symbols 14—11 337 Breaching Charge Computations 2—12 24 Breaching Minefields 3-10,3—11 75 Breaching Pavements 2—10, 2—19 21, 37 Bridge

Abutment Demolition 2—10 18 Classification 5-1 124 Demolition 2—7 9 Design 7-1 168 Marking 5—1 124 Recon Symbols 14—1 312 Recon Reports 14—2 320 Signs 5—1 125 Traffic Controls 5—1 126

Bridge, Rope 7—17,7—18 215 Bridges, Fixed 7—1 168

Classification 7—6 199 Intermediate Support 7—4 185 Nomenclature 7—1 168 Notations 7—2 168 Substructure 7—5 196 Superstructure 7—3 170

Bridges Miscellaneous Armored Vehicle Launched Bridge 7—19 215 Four Rope Bridge 7—18 215 Light Suspension Bridge 7—16 212 M4T6 Fixed Span 7—20 216 Three Rope Bridge 7—17 215

Bridges, Panel 7—9 205 Assembly and Launching 7—14 210 Design 7-11 210 Planning 7-12 210

Site Layout 7—13 210 Site Reconnaissance 7—10 205

Bridging Equipment, Float 6—1 131 Bunkers 4-5 96

Cable-Bridle Line 6-7 149 Cables, Anchorage System 6—7 149 Calcium Hypochlorite 16-2 348 Caltrop 4—23 118 Camouflage 16—6 361 Camouflage, Minefields 3—6c ®1 Caution Crossing 5—1c 127 Cement Storage 8—1 217 Cement Types 8—1 217 Chain Hoists 11—2 274 Chain Loading Scrapers 12—3b 296 Chains 11-16 291 Checkdams 9-5 238 Chespaling 9-7 250 Clamps, Wire Rope 11-5 278 Classification, Barbed Wire 4-9 105 Classification, Bridges 5—1 126 Classification, Roads 14—2b 322 Claymore Mine 3—1, 3—13 40, 78 Clearing, Construction 12-2 295 Clearing, Minefields, Areas, Routes, L.Z 3—12 Cluster, Mine 3—3a 48 Combat Engineer Vehicle (CEV) 2-15 32 Comments 1-2b 1 Communications Equipment 15—1 341 Communications Security 15—4 341 Compaction Equipment 12—6 302 Concertina Wire 4—16 H2 Concrete 8—1 217

Batching 8—5 223 Braces 8-8a 225 Curing 8—7 224

Forming 8—8 225 Mix Proportioning 8—2 218 Placing and Finishing 8—6 224

Concrete Obstacles 2-15 35 Contours, Map 16—14g 394 Conversion- English to Metric 16—17 410 Conversion Factors 16-16 399 Corduroy Roads 9—7 250 Counterforce Charge 2-10 20 Cratering Charge 2—14 28 Crossings

Caution 5—1c 127 Normal 5-1c 127 Risk 5—1c 127 Special 5-1c 127

Culvert Alignment 9-5 246 Culvert Design 9—5 238

Deadman Deadman Design Declination Diagram Defensive Position Priorities .. Deliberate Protective Minefield Deliberate Road Crater Demolitions—See Explosives Demolition Kit, M157 Density, Minefields Detection, Mines Detonating Velocity Detonation Methods Diamond Charge Ditches Ditching Double Apron Fence Downhill Dozing Downhill Loading, Scrapers . . Dozer Production

11-4 277 6-7 161 16-14 392 4-1 84 3-2 40 2—14b 31

3—10b 75 3—3a 48 3—9a 68 2-1 3 2-4 6 2-11 23 9-5 237 .2-17,12-5 37,300 ,4-13,4-14 110,111 12-3b 295 12—3b 295 12-3 295

Dragline Production 12—4 298 Drainage 9-5 237 Driftpins 16-5 360 Dump Truck Requirements 12—4 300 Dumps, Mine 3-6d 61 Dust Control 10—6 263

Earth Moving Equipment 12—1 295 Electrical Method of Detonation 2—4 7 Electrical Wiring 16—3 351 Electronic Countercounter-measure (ECCM) 15—4 346 Emplacements, Types 4—3 85 Engineer Reconnaissance 14—9 334 Engineer Resource Symbols 14—1 315 Equipment Production Rates (See specific item) Equipment Utilization 12—1b 295 Expedient Obstacles 4—23 117 Explosives

Abatis 2—13 28 Abutment Demolitions 2—10 18 Blasting Boulders 2—16 35 Breaching Charge Computations 2—12 24 Breaching Pavements 2-10,2—19 21,37 Bridge Demolitions 2—7 9 Characteristics 2—1 3 Cratering Charges 2—14 28 Detonating Velocity 2-1 3 Ditching 2-17 37 Firing Systems 2—5 8 Obstacle Destruction 2—15 32 Obstacle Planning 2—7 9 Pier Demolition 2—10 18 Priming 2-4 6 Relative Effectiveness Factors 2—1 3 Safe Distances 2—2 4 Safety 2-3 6 Steel Cutting 2-11 21

Stumping Timber Cutting . Wall Demolition

2—18 37 2-13 26 2-12,2-15 26,35

Facing Revetments 4—4 FARRP Layout 10-4 Ferry Reconnaissance 14—7 Fiber Ropes 11 — 1 Field Fortifications 4—1 Fields of Fire 4—2 Field Sanitation 13—1 Firing Devices, Mines 3—2 Firing Systems 2—4 Fixed Bridge Reconnaissance 14—3 Flame Field Expedients 16—8 Float Bridge Reconnaissance 6—1 Floating Equipment 6-1.6-2, 6—3 Floating Equipment Employed by Helicopter 6—4 Ford Reconnaissance 14- 6 Form Design, Concrete 8—8 Four Rope Bridge 7—18 Four Strand Cattle Fence 4-20 Foxhole Digger Explosive Kit 4—3 Foxholes 4—3 Functions of Numbers 16—9 Fuzed, Mines 3—1

Gaps, Minefields 3—3a Garbage Pits 13—3 General Purpose Barbed Tape Obstacle 4-18 Geometric Figures 16—10 Gin Pole 11-11, 11-12 Grade Stakes 9—3 Grader Production 12—5 Grading 12-5 Gravel Requirements 8—1,8—2 Grease Trap 13-3 Guy Line 11-14

94 259 333 271 84 84

304 40

6 325 370 131 131 131 331 225 215 115 89 85

375 40

52 308 114 377 288 231 301 300 218 309 291

425

Hand Washing Device 13—2 304 Hasty Protective Minefield 3—2 40 Hasty Road Crater 2-14d 32 Haul Roads 12—3 296 Heavy Equipment 12—1 295 Heavy Equipment Efficiency Factors 12—7 302 Heavy Equipment Selection 12—3 295 Helicopter Characteristics 10—2 256 Helicopter Ground Crew 11—9 283 Helipad Construction 10—3 256 Heliport Marking 10—7 263 Hitches 11-6 280 Holdfasts, Picket 11—3 276 Hooks 11-17 291

Infantry Weapons 16-12 380 Interdiction Minefield 3—2 47 Iodine Tablets 16—2 348 Irregular Outer Edge (IDE) 3-3a 48

Kedge Anchors 6—6 149 Knife Rest 4-22 117 Knots 11-15 291

Lag Screws 16—5 360 Landing Mat, Types 10—8 263 Landing Zone Dimensions 10—5 263 Landing Zone Layout 10—4 259 Lanes, Minefields 3—3a 52 Latrines 13—3 305 Laying Unit Organization, Minefields 3—6a 61 Lifting and Loading Equipment 12—4 296 Light Tactical Raft Data 6—1 131 Log Cribs 4-23 122 Log Hurdles 4-23 120 Log Obstacles 2—15 35 Log Scale 16—4 355

Maps 16- 14 391 Aerial Photography Supplements 16-141 397 Bar Scales 16-14d 392 Colors 16-14c 391 Contours 16-14g 394 Declination Diagram 16—14d 392 Definition 16—14 391 Distance Conversion 16—14f 394 Grid Reference Box 16-14d 392 Legend 16-14d 392 Marginal Data 16-14b 392 Orientation 16—14e, j 392, 397 Photo Map 16—14j 397 Reading 16-14 391 Representative Fraction 16—14f 394 Scale 16—14b 391 Scale Conversion 16—14f 394 Slope 16-14b 391 Types 16-14a 391

March Formulas 16—11 380 Marginal Data (Map) 16-14d 392 Marking Bridges and Vehicles 5—1,5—2 124 Marking Heliports 10—7 263 Marking Minefields 3-5a 60 Masonry Arch Bridge 7—8 204 Material Factor for Breaching 2—12 25 Mechanical Advantage 11—2 271 Metal Landing Mat Road 9—7 255 Military Road Classification 14—2 322 Mine Warfare

Authority to Lay 3—2 40 Breaching 3—10,3—11 75 Camouflage 3-6c 61 Claymore 3-1,3-13 40,78 Clearing, Area, Route, L.Z 3—12 77 Clusters 3—3a 48 Computations, Mines, Manhours, Vehicles 3—4 54 Density 3—3a 48

428

Detection 3—9a 68 Dumps 3- 6d 61 Employment 3—2 40 Firing Devices 3-1 40 Fuzes 3—1 40 Gaps 3—3a 52

IOE 3—3a 48 Lanes 3—3a 52 Laying unit Organization 3—6a 61 Marking 3—5 60 Minefields, Types 3—2 40 Mines, Types 3—1 40 Numbering of Clusters 3—3a 51 Patterns 3—3a 47 Recording 3—8 64 Removal 3—9b 68 Reports 3—7a, b 64 Row of Mines 3—3a 53 Row Mining 3—3b 53 Safety 3-14 82 Scatterable Mines 3- 2 40 Strip 3-3a 47 Strip Centerline 3—3a 47 Trip Flares 3—1 40 TripWires 3--3a 52

Minefield Strip 3—3a 47 Mixer Cleaning 8—3a 222 Mobile Assault Bridge Data 6—1 135 Movements, Troop 16—11 380 M4T6 Raft/Bridge Data 6—1, 6—2 134

Nails and Fasteners . Normal Crossing . . . Numbers, Functions

16-5 355 5—1c 127 16-9 375

Oblique Triangles 16-9 375 Obstacle Demolition

Concrete 2—15b 35 Log 2-15b 35 Steel 2-11 21 Walls 2—15c 35

Offset Stakes 9—3 231 Open Ditch Design 9-5a 237 Organic Test, Soils 9-4b 231 Overhead Cable - Bridle Line 6—7 149 Overlay Symbols 14—1 311

Phony Minefield 3-2 47 Photo Grid Coordinates 16—14 391 Photo - Ground Orientation 16—14 391 Photo Map Orientation 16—14a 391 Picket Holdfasts 11-3 276 Pictomap 16—14a 391 Pier Demolition 2—10 19 Placing Concrete 8—6 224 Planimetrie Map 16-14a 391 Plastic Relief Map 16—14a 391 Point Minefield 3-2 47 Portable Barbed Wire Obstacles 4—22 117 Portland Cement 8—la 217 Post Obstacles 4-23 121 Power Shovel Production 12—4 296 Production Rate of Equipment (See specific item) Project Management 16-15 398 Protective Minefield 3—2 40 Push Loading, Scrapers 12-3 295

Radio Location 15-3 341 Radio Transmission Format 15-5 347 Rafting Equipment 6-1 131 Rates of March 16-11 380

430

Reconnaissance Engineer 14-9 33«* Ferry 14- 7 333 Fixed Bridges 14--3 325 Float Bridges 6-1 131 Ford 14-6 331 Overlay Symbols 14 -1 312

' River 14-4 327 Road 14-2 318 Route 14-1 317 Tunnel 14--5 331 Unit Symbols 14—11 337 Water 14-8 333

Recording, Minefields 3-8 64 Enemy Minefield 3- 8c 68 Ford Mining 3—8a 64 Hasty Protective Minefield 3- 8b 68 Point Minefield 3-8a 64 Standard Pattern Minefield 3- 8a 64

Recovery, Vehicles 16- 7 367 Relative Effectiveness Factors 2—1 3 Relieved Face Crater 2-14c 32 Removal Mines 3—9b 68 Reports, Minefield 3- 7a, b 64 Representative Fraction (RF) 16- 14 393 Retaining Wall Revetments 4-4 93 Revetments, Types 4-4 93 Ribbon Bridge Data 6—1 136 Ribbon Charge 2—11 21 Ribbon Test, Soil 9—4b 237 Rigging

Attachments 11—5 278 Blocks 11-2 271 Boom Derrick 11-13 288 Chains 11 -16 291 Deadman 11—4 277 Ginpole 11-12 288

Guyline 11-14 291 Helicopter 11—8 281 Holdfast 11-3 276 Hooks 11-17 291 Knots 11-15 291 Ropes 11-1 271 Shears 11—11 287

Right Triangles 16—9 375 Ring Charge 2-13 28 Rippers 12—3b 295 Risk Crossing 5—1c 127 River Crossing Equipment 6—1 131 River Reconnaissance 14—4 327 Road Classification Formula 14—2 322 Road Construction

Cross Sections 9-1 229 Design 9-2 229 Drainage 9-5 237 Hasty Road Construction 12—5 301 Soils 9-4 231 Stakes 9-3 231

Road Reconnaissance 14—2 318 Road Specifications 9-2 229 Road Surfaces. Expedient 9—7 247 Rope Bridge 7—17 215 Ropes 11-1 271 Route Classification Formula 14—1 317 Route Reconnaissance 14—1 310 Row Mining 3—3b 53 Runoff 9—5c 240

Safety Explosives and Demolitions 2—3 6 Mine Warfare 3—14 82

Saddle Charge 2—11 22 Sand Requirements 8—1 218

432

oonitótion Facilities 13—1 304 Garbage Pits 13—3b 308 Latrines 13-3a 305 Showers 13—2b 305 Soakage Pits 13—3c 309 Washing 13—2a 304

Scales, Map 16—14b 391 Scatterable Mines 3—2 40 Scoop Loader Production 12—4 296 Scope 1—1 1 Scrapers 12—3b 296 Screws 16—5b 358 Sedimentation Test, Soils 9—4b 235 Shaking Test, Soils 9—4b 237 Shears 11-12 288 Sheathing for Concrete Forms 8—8a 226 Sheepsfoot Roller Production 12—6 302 Shelters 4-6 96 Shine Test, Soils 9—4b 236 Shoe Plates for Concrete Forms 8—8a 226 Shore Guys 6—6 149 Shoulder Stakes 9—3 231 Shower Unit 13-2 305 Shuttle Loading, Scrapers 12-3b 296 Signs, Bridge Classification 5—1b 125 Signs, Vehicle Classification 5—2b 128 Slings 11-6 280

Design 11—8 281 Helicopter 11-8 281 Load Formula 11—7 281 Stresses 11—7 280

Slope, Map 16—14h 395 Slope Stakes : 9—3 231 Slot Dozing 12—3b 295 Slump Test 8-2c 219 Soakage Pits 13-3 309

Soils 9-1 229 Characteristics 9—4a 231 Identification Tests 9—4b 231 Moisture Content 9—4 237 Conversion Factors 12-4 299 Stabilization 9—6 247

Special Crossing 5—1c 127 Specific Gravities 16—1 348 Spikes 16—5a 355 Spruce Timbers, for Ginpole 11 — 10 286 Stakes, Construction 9—3 231 Standard Minefield Pattern 3—3a 47 Steel Cutting 2—11 21 Steel Obstacle Demolition 2-11 21

Stream Velocity 14—6 331 Stream Width 14-6 331 Strip Centerline 3—3a 47

Studs for Concrete Forms 8—8a 226 Stumping 2-18 37 Symbols

Overlay 14—1 312 Unit 14-11 337 Weapons 14—11c 340

Tactical Minefield 3—2 40 Tamping Factor for Breaching 2—12 25 Tanglefoot 4—21 116 Terrain Association 16—14 394 Tetrahedron 4—23 123 Thread Test, Soils 9—4b 236 Three rope Bridge 7—17 215 Tie Wires for Concrete Forms 8—8a 226 Timber Construction, Estimating 16—4 355 Timber Cutting, Explosives 2—13 26 Time Distance Conversion 16—18 410 Topographic Map 16—14a 391

433

Towers, Anchorage 6—7b 157 Tractor Production 12—2 295 Trapezoidal Ditch 4—23 119 Tread Roads 9—7 250 Tree and Stump Blasting 2-18 37 Trigometric Functions 16—9 375 Trip Flare 3—1 40 Trip Wires 3—3a 52 Troop Movement Factors 16-11 380 Tunnel Reconnaissance 14-5 331

Unit Designation Symbols 14-11 337 Urinoil 13-3 307

Vehicle Classification 5—3 128 Vehicle Classification Signs 5—2 128 Vehicle Markings 5—2 127 Vehicle Recovery Expedients 16—7 337 Volumes of Geometric Figures 16- 10 377

Wales (Walers) for Concrete Forms 8—8a 226 Wall Destruction 2—15 35 Washing Facilities 13-2 304 Waste Disposal 13—3 305 Water - - Cement Raios 8—2 218 Water Disinfection 16-2 34g Water Quantity Requirements 16-2 351 Water Reconnaissance 14-8 333 Waterproofing, Soil 10-6 263 Weapons 16-12 380 Weapons Symbols 14—11 340 Wedge Socket 11-5 . 278 Weights and Specific Gravities 16 -1 348 Wire Mesh Reads 9_7 254

Wire Obstacles Antipersonnel 4—7 105 Antivehicular 4—7 105 Barbed Steel Tape 4—12 110 Combination Bands 4—9 105 Double Apron Fence 4—13 110 Expedient 4-23 117 Estimating Requirements 4-10 106 Four Strand Cattle Fence 4—20 115 General Purpose Barbed Tape Obstacle 4—18 114 Low Wire Fence 4—19 115 Portable Obstacles 4-22 117 Principles of Employment 4—8 105 Triple Standard Concertina 4—16 112

Wire Rope Clips 11—5 278 Wire Ropes 11 — 1 271 Wiring 16- 3 351 Wood Screws 16—5 358

24 SEPTEMBER 1976

By Order of the Secretary of the Army:

FRED C. WEYAND General, United States Army Chief of Staff

Official:

FAULT. SMITH Major General. United States Army The Adjutant Genera!

DISTRIBUTION:

Active Army, USAR, ARNG: To be distributed in accordance with DA Form 12-11 A, Requirements for Engineer Field Data (Qty rqr block no. 26).

Additional copies can be requisitioned (DA Form 17) from the US Army Adjutant General Publications Center, 2800 Eastern Boulevard, Baltimore, MD 21220.

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